05355f4ad6
This honors blink feature status ("test", "experimental", "stable")
in third_party/blink/renderer/platform/runtime_enabled_features.json5,
overriding of the default status of the corresponding chromium features,
unless the status of the chromium feature is overridden by finch trial
or command line switches.
This resolves the following problems of blink features with
status:"test", status"experimental", status:"stable" when the
corresponding chromium feature is disabled:
1. unexpected disabling of the blink feature for web tests
2. unexpected enabling of a blink feature for unit tests (in which case
the blink feature should not have a status).
This CL only affects how blink features with status are enabled with
--enable-experimental-web-platform-features
(or chrome://flags/#enable-experimental-web-platform-features)
--enable-blink-test-features when the corresponding chromium feature is
disabled by default.
This doesn't affect
1. finch experiments (which still controls the blink features through
the chromium features);
2. other command line flags that affect blink features (either directly
or indirectly through chromium features);
3. the priority relationship among 1 and 2 and the changed factors
mentioned above.
The features that will be affected by this CL have been prepared in
either of the following methods (tracked by crbug.com/1121839, based
on feedbacks in https://docs.google.com/spreadsheets/d/1DAtdbGy7XZCC_1_IXHXZKx568pw0eDlVETCtJBexqZc/edit#gid=0):
a) For features that should be enabled for web tests but were not
because of the chromium feature disabled by default, temporarily
explicitly enable it in content/child/runtime_features.cc.
An example is crrev.com/c/2380213.
These changes are removed in this CL.
b) For features that are not ready to be enabled for web tests, or are
not meaningful to be enabled for web tests (e.g. the feature is
implemented at both chromium side and blink side), the blink status
is removed to let the chromium feature fully control the blink
feature. An example is crrev.com/c/2376067.
Bug: 1048656, 1121839
Change-Id: I8b2f15e30767dce9212097f79c8c07a373af892d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2375886
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Jason Chase <chasej@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803712}
Chromium docs
This directory contains chromium project documentation in Gitiles-flavored Markdown. It is automatically rendered by Gitiles.
If you add new documents, please also add a link to them in the Document Index below.
[TOC]
Creating Documentation
Markdown documents must follow the style guide.
Preview local changes using md_browser:
# in chromium checkout
./tools/md_browser/md_browser.py
This is only an estimate. The gitiles view may differ.
Review changes online with gerrit's links to gitiles:
- Upload a patch to gerrit, or receive a review request. e.g. https://chromium-review.googlesource.com/c/572236
- View a specific .md file. e.g. https://chromium-review.googlesource.com/c/572236/2/docs/README.md
- Click on gitiles link at top of page.
This gitiles view is the authoritative view, exactly the same as will be used when committed.
Document Index
Checking Out and Building
- Linux Build Instructions - Linux
- Mac Build Instructions - MacOS
- Windows Build Instructions - Windows
- Android Build Instructions - Android target (on a Linux host)
- Cast Build Instructions - Cast target (on a Linux host)
- Cast for Android Build Instructions - Cast for Android (on a Linux host)
- Fuchsia Build Instructions - Fuchsia target (on a Linux host)
- iOS Build Instructions - iOS target (on a MacOS host)
- Chrome OS Build Instructions - Chrome OS
- Linux Chromium ARM Recipes - Recipes for building Chromium for ARM on Linux.
- Chrome Component Build - Faster builds using more libraries
- Using the BuildRunner - Scripts that extract build stops from builders and runs them locally on a slave
- Cr User Manual - Manual for
cr, a tool that tries to hide some of the tools used for working on Chromium behind an abstraction layer
Design Docs
- See design/README.md
Integrated Development Environment (IDE) Set Up Guides
- Android Studio - Android Studio for Android builds
- Atom - Atom multi-platform code editor
- CLion - CLion IDE, supports GUI debugging.
- Eclipse for Android - Eclipse for Android
- Eclipse for Linux - Eclipse for other platforms (This guide was written for Linux, but is probably usable on Windows/MacOS as well)
- EMACS Notes - EMACS commands/styles/tool integrations
- Qt Creator - Using Qt Creator as an IDE or GUI debugger
- Visual Studio Code - Visual Studio Code
Git
- Git Cookbook - A collection of git recipes for common tasks
- Git Tips - More git tips
Clang
- Clang Compiler - General information on the clang compiler, used by default on Mac and Linux
- Clang Tool Refactoring - Leveraging clang tools to perform refactorings that are AST-aware
- The Clang Static Analyzer - How to enable static analysis at build time
- Clang Code Coverage Wrapper - Enable Clang code coverage instrumentation for a subset of source files.
- Writing Clang Plugins - Don't write a clang plugin, but if you do, read this
- Updating Clang - Updating the version of Clang used to build
- Using clang-format on Chromium C++ Code - Various ways to invoke clang-format on C++ code
- Clang Tidy - Support for the
clang-tidytool in Chromium - Updating Clang Format Binaries - How up update the clang-format binaries that come with a checkout of Chromium
General Development
- Contributing to Chromium - Reference workflow process for contributing to the Chromium code base.
- Commit Checklist - Streamlined checklist to go through before uploading CLs on Gerrit.
- Code Reviews - Code review requirements and guidelines
- Respectful Code Reviews - A guide for code reviewers
- Respectful Changes - A guide for code authors
- Mandatory Code-Review Rollout - Upcoming policy changes related to code review and OWNERS
- LUCI Migration FAQ - FAQ on Buildbot-to-LUCI builder migration for Chromium
- Tour of Continuous Integration UI - A tour of our the user interface for LUCI, our continuous integration system
- Parsing Test Results - An introduction for how to understand the results emitted by polygerrit and CI builds.
- Closure Compilation - The Closure JavaScript compiler
- Threading and Tasks in Chrome - How to run tasks and handle thread safety in Chrome.
- Callback<> and Bind() - All about Callbacks, Closures, and Bind().
- Views Platform Styling - How views are styled to fit in different native platforms
- Tab Helpers - Using WebContents/WebContentsObserver to add features to browser tabs.
- Adding third_party Libraries - How to get code into third_party/
- Graphical Debugging Aid for Chromium Views - Visualizing view trees during debugging
- Bitmap Pipeline - How bitmaps are moved from the renderer to the screen.
- base::Optional - How to use
base::Optionalin C++ code. - Using the Origin Trials Framework - A framework for conditionally enabling experimental APIs for testing.
ClientTagBasedModelTypeProcessorin Unified Sync and Storage - Notes on the central data structure used in Chrome Sync.- Chrome Sync's Model API - Data models used for syncing information across devices using Chrome Sync.
- Ozone Overview - Ozone is an abstraction layer between the window system and low level input and graphics.
- Optimizing Chrome Web UIs - Notes on making webuis more performant
- Adding a new feature flag in chrome://flags - Quick guide to add a new feature flag to experiment your feature.
- Guidelines for considering branch dates in project planning - What to do (and not to do) around branch dates when scheduling your project work.
- WebUI Explainer - An explanation of C++ and JavaScript infrastructural code for Chrome UIs implemented with web technologies (i.e. chrome:// URLs).
- Watchlists - Use watchlists to get notified of CLs you are interested in.
- Shutdown - Explains the steps of Chrome shutdown, to make it easier to determine where to add a new shutdown operation.
Testing
- Running and Debugging Web Tests
- Writing Web Tests - Web Tests using
content_shell - Web Test Expectations and Baselines - Setting expected results of web tests.
- Web Tests Tips - Best practices for web tests
- Web Tests with Manual Fallback - Writing tests that simulate manual interventions
- Extending the Web Test Framework
- Fixing Web Test Flakiness - Diagnosing and fixing web test flakiness due to ordering dependencies.
- Running Web Tests using
content_shell- Running web tests by hand. - Web Platform Tests - Shared tests across browser vendors
- Using Crashpad with
content_shell- Capture stack traces on layout test crashes without an attached debugger - Test Descriptions - Unit test targets that can be built, with associated desciptions.
- Fuzz Testing - Fuzz testing in Chromium.
- IPC Fuzzer - Fuzz testing of Chromium IPC interfaces.
- Running Chrome tests with AddressSanitizer (asan) and LeakSanitizer (lsan) - Run Chrome tests with ASAN and LSAN builds to detect addressability issues and memory leaks.
- Code Coverage - Code coverage for Chromium.
- Code Coverage in Gerrit - Per-CL code coverage in Gerrit to assist code reviews.
GPU-related docs
- GPU Pixel Wrangling - Instructions for GPU pixel wrangling (the GPU sheriffing rotation).
- Debugging GPU related code - Hints for debugging GPU- and graphics-related code.
- GPU Testing - Description of Chromium's GPU testing infrastructure.
- GPU Bot Details - In-depth description of how the bots are maintained.
Misc Linux-Specific Docs
- Linux Proxy Config - Network proxy sources on Linux
- Debugging SSL on Linux - Tips on debugging SSL code in Linux
- Linux Cert Managment - Managing X.509 Certificates in Linux
- Tips for Debugging on Linux
- Linux GTK Theme Integration - Having Chrome match the GTK+ theme.
- Browser Plugins on Linux - A collection of links to information on how browser plugins work on Linux
- Linux Crash Dumping - How Breakpad uploads crash reports to Google crash servers.
- Linux Minidump to Core - How to convert a Breakpad-generated minidump files to a core file readable by most debuggersx
- Linux Sandbox IPC - The lower level UPC system used to route requests from the bottom of the call stack up into the browser.
- Linux Dev Build as Default Browser - How to configure a Dev build of Chrome as the default browser in Linux.
- Linux Chromium Packages - Packages of Chromium browser (not Chrome) provided by some Linux distributions.
seccompSandbox Crash Dumping - Notes on crash dumping a process running in a seccomp sandbox.- Linux Password Storage - Keychain integrations between Chromium and Linux.
- Linux Sublime Development - Using Sublime as an IDE for Chromium development on Linux.
- Building and Debugging GTK - Building Chromium against GTK using lower optimization levels and/or more debugging symbols.
- Debugging GTK - Using the GTK Debug packages and related tools.
- Chroot Notes - Setting up a chroot to work around libfreetype differences in some versions of Linux.
- Linux Sandboxing - The Linux multi-process model to isolate browser components with different privileges.
- Zygote Process - How the Linux Zygote process, used to spawn new processes, works.
- Running Web Tests on Linux - Linux-specific instructions for running web tests.
- Linux Sysroot Images - How builds use libraries on Linux
- Linux Hardware Video Decoding - Enabling hardware video decode codepaths on Linux
Misc MacOS-Specific Docs
- Using CCache on Mac - Speed up builds on Mac using ccache with clang/ninja
- Cocoa tips and tricks - A collection of idioms used when writing Cocoa views and controllers
- MacViews Release Plan
Misc Windows-Specific Docs
- Handling cygwin rebaseall failures
- Hacking on ANGLE in Chromium - OpenGL ES 2.0 built on top of DirectX
- Windows Split DLLs - Splitting
chrome.dllinto multiple dlls to work around toolchain limitations on Windows.
Misc Android-Specific Docs
- Google Play Services in Chrome for Android
- Accessing C++ Enums in Java - How to use C++-defined enums in Java code
- Profiling Content Shell on Android -
Setting up profiling for
content_shellon Android - Working Remotely with Android - Building on a remote machine for an Android device connected to your local machine
- Android Test Instructions - Running a build on an Android device or emulator.
- Android Debugging - Tools and tips for how to debug Java and/or C/C++ code running on Android.
- Android Logging - How Chrome's logging API works with
android.util.Logon Android, and usage guidelines. - Chromoting Android Hacking - Viewing the logs and debugging the Chrome Remote Desktop Android client.
- Android Java Static Analysis - Catching Java related issues at compile time with the 'lint' tool.
- Java Code Coverage - Collecting code coverage data with the EMMA tool.
- Android BuildConfig files - What are .build_config files and how they are used.
- Android App Bundles - How to build Android app bundles for Chrome.
- Dynamic Feature Modules (DFMs) - How to create dynamic feature modules.
- Chrome for Android UI - Resources and best practices for developing UI
Misc iOS-Specific Docs
- Continuous Build and Test Infrastructure for Chromium for iOS
- Opening links in Chrome for iOS - How to have your iOS app open links in Chrome.
- User Agent in Chrome for iOS - Notes on User Agent strings using Chrome for iOS.
- Running iOS test suites locally
- Working With Project Files in iOS - How to add, remove, and rename files in the iOS Chromium project.
Misc Chrome-OS-Specific Docs
- Setting up captive portals and other restrictive networks
- Enterprise Enrollment
- Debugging UI in OOBE/login/lock
- Chrome Logging on Chrome OS
Misc WebUI-Specific Docs
- Creating WebUI Interfaces in components/ How to
create a new WebUI component in the
components/directory.
Media
- Audio Focus Handling - How multiple MediaSession audio streams interact
- Autoplay of HTMLMediaElements - How HTMLMediaElements are autoplayed.
- Piranha Plant - Future architecture of MediaStreams
- Video Encode Accelerator Tests - How to use the accelerated video encoder test program.
- Video Decoder Tests - Running the video decoder tests.
- Video Decoder Performance Tests - Running the video decoder performance tests.
Accessibility
- Accessibility Overview - Overview of accessibility concerns and approaches in Chromium.
- Accessibility Tests - Where to find accessibility-related tests in the codebase.
- ChromeVox on Chrome OS - Enabling spoken feedback (ChromeVox) on Chrome OS.
- ChromeVox on Desktop Linux - Enabling spoken feedback (ChromeVox) on desktop Linux.
- Offscreen, Invisible and Size - How Chrome defines offscreen, invisible and size in the accessibility tree.
- Text to Speech - Overview of text to speech in Chrome and Chrome OS.
- BRLTTY in Chrome OS - Chrome OS integration with BRLTTY to support refreshable braille displays
- PATTS on Chrome OS - Notes on the PATTS speech sythesis engine used on Chrome OS
- VoiceOver - Using Apple's VoiceOver feature with Chromium on iOS.
Memory
Memory Infrastructure Timeline Profiling (MemoryInfra)
- Overview
- GPU Profiling
- Adding Tracing to a Component
- Enabling Startup Tracing
- Memory Usage in CC
- Memory Benchmarks
- Heap Profiling
Misc
- Useful URLs - A collection of links to various tools and dashboards
- ERC IRC - Using ERC in EMACS to access IRC
- Kiosk Mode - Simulating kiosk mode.
- User Handle Mapping - Names of developers across Chromium/IRC/Google
- Documentation Best Practices
- Documentation Guidelines
- Chromium Browser vs Google Chrome - What's the difference between Chromium Browser and Google Chrome?
- Google Chrome branded builds
- Proxy Auto Config using WPAD - How WPAD servers are used to automatically set proxy settings.
- Installing Chromium OS on VMWare - How to install Chromium OS on VMWare.
- User Data Directory - How the user data and cache directories are determined on all platforms.
- User Data Storage - Policy documentation for files in User Data.
Mojo & Services
- Intro to Mojo & Services - Quick introduction to Mojo and services in Chromium, with examples
- Mojo API Reference - Detailed reference documentation for all things Mojo
- Service Development Guidelines - Guidelines for service development in the Chromium tree
- Servicifying Chromium Features - General advice for integrating new and existing subsystems into Chromium as services
- Converting Legacy IPC to Mojo - Tips and common patterns for practical IPC conversion work
- Mojo “Style” Guide - Recommendations for best practices from Mojo and IPC reviewers
Speed
- Chrome Speed - Documentation for performance measurements and regressions in Chrome.
- Chrome Speed Metrics - Documentation about user experience metrics in the web and their JavaScript APIs.
WebXR
- Running OpenVR Without Headset - Instructions for running OpenVR on Windows without a headset
Probably Obsolete
- TPM Quick Reference - Trusted Platform Module notes.
- System Hardening Features - A list of current and planned Chrome OS security features.
- WebView Policies
- Linux Profiling - How to profile Chromium on Linux
- Linux Graphics Pipeline
- Linux
SUIDSandbox - Sandboxing renderers using a SUID binary on Linux - Linux
SUIDSandbox Development - Development on the above system. - Linux PID Namespace Support
- Vanilla msysgit workflow - A workflow for using mostly vanilla git on Windows.
- Old Chromoting Build Instructions
- Old Options - Pre-Material Design chrome://settings notes.