Cleanup: Remove documentation referring to the linux_breakpad GYP flag.

Review URL: https://codereview.chromium.org/1376253004

Cr-Commit-Position: refs/heads/master@{#351858}

components/crash/content/app/breakpad_linux_impl.h

@@ -3,8 +3,7 @@
 // found in the LICENSE file.
 
 // Internal header file for the Linux breakpad implementation. This file is
-// shared between crash_handler_host_linux.cc and breakpad_linux.cc. It should
-// only be used in files compiled with linux_breakpad=1.
+// shared between crash_handler_host_linux.cc and breakpad_linux.cc.
 
 #ifndef COMPONENTS_CRASH_CONTENT_APP_BREAKPAD_LINUX_IMPL_H_
 #define COMPONENTS_CRASH_CONTENT_APP_BREAKPAD_LINUX_IMPL_H_

docs/linux_crash_dumping.md

@@ -116,12 +116,7 @@ display the sad tab.
 
 ## How to test Breakpad support in Chromium
 
-*   Build Chromium with the gyp option `-Dlinux_breakpad=1`.
-
-    ```shell
-    ./build/gyp_chromium -Dlinux_breakpad=1
-    ninja -C out/Debug chrome
-    ```
+*   Build Chromium as normal.
 *   Run the browser with the environment variable
     [CHROME_HEADLESS=1](https://crbug.com/19663). This enables crash dumping but
     prevents crash dumps from being uploaded and deleted.
@@ -129,7 +124,7 @@ display the sad tab.
     ```shell
     env CHROME_HEADLESS=1 ./out/Debug/chrome-wrapper
     ```
-*   Visit the special URL `about:crash` to trigger a crash in the renderer
+*   Visit the special URL `chrome://crash` to trigger a crash in the renderer
     process.
 *   A crash dump file should appear in the directory
     `~/.config/chromium/Crash Reports`.