Fix use_static_angle build flag and require a flag to use ANGLE.

ui/gl initialization is now in a sub library, move the dependencies.

Require a flag to use ANGLE on Android, this allows ANGLE and the native
driver to both work with a given build so we can test on the bots.

BUG=726002

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I2d3e0c4e844dca9e72c363f07e011c710e1a9f57
Reviewed-on: https://chromium-review.googlesource.com/c/1244078Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596236}

ui/gl/BUILD.gn

@@ -201,10 +201,6 @@ jumbo_component("gl") {
         "gl_surface_egl_surface_control.cc",
         "gl_surface_egl_surface_control.h",
       ]
-
-      if (use_static_angle) {
-        deps += [ "//third_party/angle:libEGL_static" ]
-      }
     }
 
     if (is_posix && !is_fuchsia && !is_mac) {

ui/gl/init/BUILD.gn

@@ -4,6 +4,7 @@
 
 import("//build/config/jumbo.gni")
 import("//build/config/ui.gni")
+import("//ui/gl/features.gni")
 
 jumbo_component("init") {
   output_name = "gl_init"
@@ -38,6 +39,10 @@ jumbo_component("init") {
       "gl_factory_android.cc",
       "gl_initializer_android.cc",
     ]
+
+    if (use_static_angle) {
+      deps += [ "//third_party/angle:libEGL_static" ]
+    }
   } else if (is_win && !use_ozone) {
     sources += [
       "gl_factory_win.cc",

ui/gl/init/gl_initializer_android.cc

@@ -24,13 +24,17 @@ namespace init {
 
 namespace {
 
-bool InitializeStaticEGLInternal() {
 #if BUILDFLAG(USE_STATIC_ANGLE)
+bool InitializeStaticANGLEEGLInternal() {
 #pragma push_macro("eglGetProcAddress")
 #undef eglGetProcAddress
   SetGLGetProcAddressProc(&eglGetProcAddress);
 #pragma pop_macro("eglGetProcAddress")
-#else   // BUILDFLAG(USE_STATIC_ANGLE)
+  return true;
+}
+#endif  // BUILDFLAG(USE_STATIC_ANGLE)
+
+bool InitializeStaticNativeEGLInternal() {
   base::NativeLibrary gles_library = LoadLibraryAndPrintError("libGLESv2.so");
   if (!gles_library)
     return false;
@@ -54,7 +58,32 @@ bool InitializeStaticEGLInternal() {
   SetGLGetProcAddressProc(get_proc_address);
   AddGLNativeLibrary(egl_library);
   AddGLNativeLibrary(gles_library);
+
+  return true;
+}
+
+bool InitializeStaticEGLInternal() {
+  bool initialized = false;
+
+#if BUILDFLAG(USE_STATIC_ANGLE)
+  const base::CommandLine* command_line =
+      base::CommandLine::ForCurrentProcess();
+  // Use ANGLE if it is requested via the --use-gl=angle flag and it is
+  // statically linked
+  if (command_line->GetSwitchValueASCII(switches::kUseGL) ==
+      kGLImplementationANGLEName) {
+    initialized = InitializeStaticANGLEEGLInternal();
+  }
 #endif  // BUILDFLAG(USE_STATIC_ANGLE)
+
+  if (!initialized) {
+    initialized = InitializeStaticNativeEGLInternal();
+  }
+
+  if (!initialized) {
+    return false;
+  }
+
   SetGLImplementation(kGLImplementationEGLGLES2);
 
   InitializeStaticGLBindingsGL();