Move ANGLE to flutter/third_party (#51270)

This moves Flutter out of the buildroot's third_party directory and into
//flutter/third_party and updates all BUILD and gni files.

Issue: flutter/flutter#144786
Part of: flutter/flutter#67373

## Pre-launch Checklist

- [X] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [X] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [X] I read and followed the [Flutter Style Guide] and the [C++,
Objective-C, Java style guides].
- [X] I listed at least one issue that this PR fixes in the description
above.
- [X] I added new tests to check the change I am making or feature I am
adding, or the PR is [test-exempt]. See [testing the engine] for
instructions on writing and running engine tests.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [X] The odds of this passing on its first CI run is 0%, because
there's no way the licence script isn't going to have a fit over it, at
which point I promise on my honour that I will dutifully fix all the
things it complains about and re-run, probably more than once.
- [X] This PR fulfils the minimum [Canadian
Content](https://www.youtube.com/watch?v=h9NMnPm5kXc&list=PLJ7QPuvv91JuoPWrLhqX0zDFUoLdynMEk&index=3)
regulations mandated by the CRTC.
- [X] I signed the [CLA].
- [X] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#overview
[Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene
[test-exempt]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[C++, Objective-C, Java style guides]:
https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style
[testing the engine]:
https://github.com/flutter/flutter/wiki/Testing-the-engine
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes
[Discord]: https://github.com/flutter/flutter/wiki/Chat

DEPS

@@ -677,7 +677,7 @@ deps = {
    'src/flutter/third_party/swiftshader':
    Var('swiftshader_git') + '/SwiftShader.git' + '@' + '2fa7e9b99ae4e70ea5ae2cc9c8d3afb43391384f',
 
-   'src/third_party/angle':
+   'src/flutter/third_party/angle':
    Var('chromium_git') + '/angle/angle.git' + '@' + '6a09e41ce6ea8c93524faae1a925eb01562f53b1',
 
    'src/third_party/vulkan_memory_allocator':

build_overrides/angle.gni

@@ -7,7 +7,7 @@ import("//build/toolchain/toolchain.gni")
 
 # The ANGLE build requires this file to point to the location of third-party
 # dependencies.
-angle_root = "//third_party/angle"
+angle_root = "//flutter/third_party/angle"
 
 angle_vma_version = 30000001
 

ci/licenses.sh

@@ -162,7 +162,7 @@ function verify_licenses() (
 
   local actualLicenseCount
   actualLicenseCount="$(tail -n 1 flutter/ci/licenses_golden/licenses_flutter | tr -dc '0-9')"
-  local expectedLicenseCount=843 # When changing this number: Update the error message below as well describing the newly expected license types.
+  local expectedLicenseCount=878 # When changing this number: Update the error message below as well describing the newly expected license types.
 
   if [[ $actualLicenseCount -ne $expectedLicenseCount ]]; then
     echo "=============================== ERROR ==============================="

ci/licenses_golden/tool_signature

@@ -1,2 +1,2 @@
-Signature: 6869bf83ae9a2e71a9302f51626429a0
+Signature: 3d3a0db1d0e7f5b2fe1f3739e50795f8
 

impeller/golden_tests/BUILD.gn

@@ -83,10 +83,10 @@ if (is_mac) {
       "//flutter/impeller/aiks",
       "//flutter/impeller/aiks:aiks_unittests_golden",
       "//flutter/impeller/fixtures",
+      "//flutter/third_party/angle:libEGL",
+      "//flutter/third_party/angle:libGLESv2",
       "//flutter/third_party/googletest:gtest",
       "//flutter/third_party/swiftshader",
-      "//third_party/angle:libEGL",
-      "//third_party/angle:libGLESv2",
     ]
   }
 }

impeller/renderer/backend/gles/BUILD.gn

@@ -8,7 +8,7 @@ import("../../../tools/impeller.gni")
 config("gles_config") {
   # Generic GL/GLES/EGL/Vulkan headers. Any will do. We just pick one from Angle
   # because they are there.
-  include_dirs = [ "//third_party/angle/include" ]
+  include_dirs = [ "//flutter/third_party/angle/include" ]
 }
 
 impeller_component("gles_unittests") {
@@ -85,11 +85,11 @@ impeller_component("gles") {
   if (!is_android && !is_fuchsia) {
     public_configs = [ ":gles_config" ]
     sources += [
-      "//third_party/angle/include/GLES2/gl2ext.h",
+      "//flutter/third_party/angle/include/GLES2/gl2ext.h",
 
       # The GLES3 API is a superset of GLES2. Although we target GLES2, we use
       # some GLES3 features if the driver supports them.
-      "//third_party/angle/include/GLES3/gl3.h",
+      "//flutter/third_party/angle/include/GLES3/gl3.h",
     ]
   }
 

shell/common/BUILD.gn

@@ -354,9 +354,9 @@ if (enable_unittests) {
 
     if (shell_enable_gl) {
       deps += [
+        "//flutter/third_party/angle:libEGL_static",
+        "//flutter/third_party/angle:libGLESv2_static",
         "//flutter/third_party/swiftshader",
-        "//third_party/angle:libEGL_static",
-        "//third_party/angle:libGLESv2_static",
       ]
     }
   }

shell/platform/windows/BUILD.gn

@@ -11,7 +11,7 @@ _public_headers = [ "public/flutter_windows.h" ]
 _internal_headers = [ "flutter_windows_internal.h" ]
 
 config("relative_angle_headers") {
-  include_dirs = [ "//third_party/angle/include" ]
+  include_dirs = [ "//flutter/third_party/angle/include" ]
 }
 
 # Any files that are built by clients (client_wrapper code, library headers for
@@ -138,7 +138,7 @@ source_set("flutter_windows_source") {
 
   configs += [
     "//flutter/shell/platform/common:desktop_library_implementation",
-    "//third_party/angle:gl_prototypes",
+    "//flutter/third_party/angle:gl_prototypes",
   ]
 
   public_configs = [ ":relative_angle_headers" ]
@@ -161,13 +161,13 @@ source_set("flutter_windows_source") {
     "//flutter/shell/platform/common/client_wrapper:client_wrapper",
     "//flutter/shell/platform/embedder:embedder_as_internal_library",
     "//flutter/shell/platform/windows/client_wrapper:client_wrapper_windows",
+
+    # libEGL_static MUST be ordered before libGLESv2_static in this list. If
+    # reversed, a linker error will occur, reporting DllMain already defined in
+    # LIBCMTD.lib
+    "//flutter/third_party/angle:libEGL_static",
+    "//flutter/third_party/angle:libGLESv2_static",
     "//flutter/third_party/rapidjson",
-    "//third_party/angle:libEGL_static",  # the order of libEGL_static and
-                                          # libGLESv2_static is important.. if
-                                          # reversed, will cause a linker error
-                                          # DllMain already defined in
-                                          # LIBCMTD.lib
-    "//third_party/angle:libGLESv2_static",
   ]
 }
 

testing/BUILD.gn

@@ -259,13 +259,13 @@ if (use_swiftshader) {
 
     configs -= [ "//build/config/clang:extra_warnings" ]
     configs += [
-      "//third_party/angle:gl_prototypes",
+      "//flutter/third_party/angle:gl_prototypes",
       "//flutter/third_party/swiftshader:swiftshader_config",
     ]
     deps += [
+      "//flutter/third_party/angle:libEGL_static",
+      "//flutter/third_party/angle:libGLESv2_static",
       "//flutter/third_party/swiftshader",
-      "//third_party/angle:libEGL_static",
-      "//third_party/angle:libGLESv2_static",
     ]
   }
 }

tools/licenses/lib/paths.dart

@@ -30,6 +30,17 @@ final Set<String> skippedPaths = <String>{
   r'flutter/lib/web_ui/dev', // these are build tools; they do not end up in Engine artifacts
   r'flutter/prebuilts',
   r'flutter/sky/packages/sky_engine/LICENSE',
+  r'flutter/third_party/angle/android',
+  r'flutter/third_party/angle/doc',
+  r'flutter/third_party/angle/extensions',
+  r'flutter/third_party/angle/infra',
+  r'flutter/third_party/angle/scripts',
+  r'flutter/third_party/angle/src/libANGLE/renderer/metal/doc',
+  r'flutter/third_party/angle/src/libANGLE/renderer/vulkan/doc',
+  r'flutter/third_party/angle/src/third_party/volk', // We don't use Vulkan in our ANGLE build.
+  r'flutter/third_party/angle/third_party', // Unused by Flutter: BUILD files with forwarding targets (but no code).
+  r'flutter/third_party/angle/tools', // These are build-time tools, and aren't shipped.
+  r'flutter/third_party/angle/util',
   r'flutter/third_party/benchmark', // only used by tests
   r'flutter/third_party/boringssl/src/crypto/err/err_data_generate.go',
   r'flutter/third_party/boringssl/src/fuzz', // testing tools, not shipped
@@ -161,17 +172,6 @@ final Set<String> skippedPaths = <String>{
   r'out', // output of build
   r'third_party/android_embedding_dependencies', // Not shipped. Used only for the build-time classpath, and for the in-tree testing framework for Android
   r'third_party/android_tools', // excluded on advice
-  r'third_party/angle/android',
-  r'third_party/angle/doc',
-  r'third_party/angle/extensions',
-  r'third_party/angle/infra',
-  r'third_party/angle/scripts',
-  r'third_party/angle/src/libANGLE/renderer/metal/doc',
-  r'third_party/angle/src/libANGLE/renderer/vulkan/doc',
-  r'third_party/angle/src/third_party/volk', // We don't use Vulkan in our ANGLE build.
-  r'third_party/angle/third_party', // Unused by Flutter: BUILD files with forwarding targets (but no code).
-  r'third_party/angle/tools', // These are build-time tools, and aren't shipped.
-  r'third_party/angle/util',
   r'third_party/dart/benchmarks', // not shipped in binary
   r'third_party/dart/build', // not shipped in binary
   r'third_party/dart/docs', // not shipped in binary
@@ -461,11 +461,11 @@ final List<Pattern> skippedFilePatterns = <Pattern>[
   RegExp(r'^flutter/lib/web_ui/lib/assets/ahem\.ttf$', expectNoMatch: true), // this gitignored file exists only for testing purposes
   RegExp(r'^flutter/sky/packages/sky_engine/LICENSE$'), // that is the output of this script
   RegExp(r'^flutter/third_party/abseil-cpp/(?:.+/)*[^/]+_test\.[^/]+$'),
+  RegExp(r'^flutter/third_party/angle/(?:.+/)*[^/]+_unittest\.[^/]+$'),
   RegExp(r'^flutter/third_party/boringssl/(?:.+/)*[^/]+_test\.[^/]+$'),
   RegExp(r'^flutter/third_party/boringssl/src/crypto/fipsmodule/bn/[^/]+.go$'),
   RegExp(r'^flutter/third_party/boringssl/src/crypto/fipsmodule/ec/[^/]+.go$'),
   RegExp(r'^flutter/third_party/freetype2/docs/(?!FTL\.TXT$).+'), // ignore all documentation except the license
-  RegExp(r'^third_party/angle/(?:.+/)*[^/]+_unittest\.[^/]+$'),
   RegExp(r'^third_party/dart/(?:.+/)*[^/]+_test\.[^/]+$'),
   RegExp(r'^third_party/zlib/(?:.+/)*[^/]+_unittest\.[^/]+$'),
 ];