linux: Do not checkout mutter sources by default

Mutter and its dependencies in third_party are currently checked out by
default on linux, which require an additional 300 MB disk space.

Since developers don't need to run these tests locally most of the time,
add the option to checkout the mutter sources by explicitly setting
`checkout_mutter` .gclient custom var.

Bug: 401977530
Change-Id: I83a976c7a15da69e7c3a6e86fe0dca8966cd339c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6338729
Reviewed-by: Maksim Sisov <msisov@igalia.com>
Commit-Queue: Orko Garai <orko@igalia.com>
Reviewed-by: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1431078}

.gitmodules

@@ -902,24 +902,24 @@
 [submodule "third_party/libdisplay-info/src"]
 	path = third_party/libdisplay-info/src
 	url = https://chromium.googlesource.com/external/gitlab.freedesktop.org/emersion/libdisplay-info
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter
 [submodule "third_party/libinput/src"]
 	path = third_party/libinput/src
 	url = https://chromium.googlesource.com/external/gitlab.freedesktop.org/libinput/libinput
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter
 [submodule "third_party/gvdb/src"]
 	path = third_party/gvdb/src
 	url = https://chromium.googlesource.com/external/gitlab.gnome.org/GNOME/gvdb
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter
 [submodule "third_party/glib/src"]
 	path = third_party/glib/src
 	url = https://chromium.googlesource.com/external/gitlab.gnome.org/GNOME/glib
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter
 [submodule "third_party/libgudev/src"]
 	path = third_party/libgudev/src
 	url = https://chromium.googlesource.com/external/gitlab.gnome.org/GNOME/libgudev
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter
 [submodule "third_party/mutter/src"]
 	path = third_party/mutter/src
 	url = https://chromium.googlesource.com/external/gitlab.gnome.org/GNOME/mutter
-	gclient-condition = checkout_linux
+	gclient-condition = checkout_linux and checkout_mutter

DEPS

@@ -45,6 +45,7 @@ gclient_gn_args = [
   'checkout_copybara',
   'checkout_glic_e2e_tests',
   'checkout_ios_webkit',
+  'checkout_mutter',
   'checkout_nacl',
   'checkout_openxr',
   'checkout_src_internal',
@@ -113,6 +114,10 @@ vars = {
   # output.
   'checkout_js_coverage_modules': True,
 
+  # Checkout out mutter and its dependencies to be able to run tests like
+  # interactive_ui_tests on the linux/wayland compositor.
+  'checkout_mutter': False,
+
   # Check out and download nacl for ChromeOS only.
   # This can be disabled e.g. with custom_vars.
   'checkout_nacl': 'checkout_chromeos',
@@ -2031,12 +2036,12 @@ deps = {
 
   'src/third_party/glib/src': {
       'url': Var('chromium_git') + '/external/gitlab.gnome.org/GNOME/glib.git' + '@' + '95eafc073843cb6e8c848f3850c074a83e01427c',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   'src/third_party/gvdb/src': {
       'url': Var('chromium_git') + '/external/gitlab.gnome.org/GNOME/gvdb.git' + '@' + 'b54bc5da25127ef416858a3ad92e57159ff565b3',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   'src/third_party/freetype/src':
@@ -2314,7 +2319,7 @@ deps = {
 
   'src/third_party/libdisplay-info/src': {
       'url': Var('chromium_git') + '/external/gitlab.freedesktop.org/emersion/libdisplay-info.git' + '@' + '66b802d05b374cd8f388dc6ad1e7ae4f08cb3300',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   # Userspace interface to kernel DRM services.
@@ -2325,12 +2330,12 @@ deps = {
 
   'src/third_party/libgudev/src': {
       'url': Var('chromium_git') + '/external/gitlab.gnome.org/GNOME/libgudev.git' + '@' + 'df7c9c9940160307aaeb31347f4776a46f8736a9',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   'src/third_party/libinput/src': {
       'url': Var('chromium_git') + '/external/gitlab.freedesktop.org/libinput/libinput.git' + '@' + '3aa004b96488bf0b2446c11b97a7f8a75ff37c23',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   'src/third_party/expat/src':
@@ -2451,7 +2456,7 @@ deps = {
 
   'src/third_party/mutter/src': {
       'url': Var('chromium_git') + '/external/gitlab.gnome.org/GNOME/mutter.git' + '@' + '30b7162b54de7681fb585d095de8a5ffaf771d38',
-      'condition': 'checkout_linux',
+      'condition': 'checkout_linux and checkout_mutter',
   },
 
   'src/third_party/nasm': {

docs/ozone_overview.md

@@ -309,19 +309,33 @@ you can use a locally compiled version of Weston or Mutter. This is what the
 build bots do. Please note that this is required for interactive_ui_tests, as
 those tests use a patched version of the compositor.
 
-Add this to your gn args:
+Mutter and its dependencies are not checked out by default to keep the disk
+usage optimal for most developers. In order to checkout mutter, add the
+`checkout_mutter` custom var in your .gclient file and set it to `True` and run `gclient sync`.
+
+```
+solutions = [
+  {
+    "url": "https://chromium.googlesource.com/chromium/src.git",
+    "managed": False,
+    "name": "src",
+    "custom_deps": {},
+    "custom_vars": {
+      "checkout_mutter": True,
+    },
+  },
+]
+```
+
+For weston, simply add this to your gn args:
 
 ``` shell
-# For weston
 use_bundled_weston = true
 ```
 
-``` shell
-# For mutter
-use_bundled_mutter = true
-```
 
-Then run the xvfb.py wrapper script and tell it to start the compositor with the tests:
+Then after building the test executable, run the xvfb.py wrapper script and tell
+it to start the compositor with the tests:
 
 ``` shell
 cd out/debug  # or your out directory

testing/xvfb.py

@@ -611,6 +611,18 @@ def _weston_config_file_path():
 
 
 def _run_with_mutter(cmd, env, stdoutfile, cwd):
+  # Ensure mutter is checked out first.
+  if not os.path.isdir(
+      os.path.join(os.path.dirname(__file__), '..', 'third_party', 'mutter',
+                   'src')):
+    print(
+        'In order to run tests using mutter, its sources need to be checked out'
+        ' explicitly and built.\n'
+        'Add \'"checkout_mutter": True\' in the "custom_vars" section of your'
+        ' .gclient file, and run gclient sync.\n'
+        'Then build the test executable or mutter and run this script again.',
+        file=sys.stderr)
+    return 1
   with dbus_session(env):
     mutter_proc = None
 

ui/ozone/platform/wayland/wayland.gni

@@ -17,5 +17,10 @@ declare_args() {
   use_bundled_weston = false
 
   # Checks if mutter must be compiled
-  use_bundled_mutter = false
+  use_bundled_mutter = checkout_mutter
 }
+
+assert(
+    !use_bundled_mutter || checkout_mutter,
+    "'use_bundled_mutter' gn arg is set to true but sources not checked out. " +
+        "Set 'checkout_mutter' custom var in .gclient and run gclient sync.")