ui: Allow individual test suites to opt-out of the TestCompositor.

ui/gl/gl_surface.cc

Index: ui/gl/gl_surface.cc
diff --git a/ui/gl/gl_surface.cc b/ui/gl/gl_surface.cc
index c08da8c3462e37875f7532b7deb351d9839bb27e..b58fc13b02b3eb416edb10baea3b59d796813605 100644
--- a/ui/gl/gl_surface.cc
+++ b/ui/gl/gl_surface.cc
@@ -95,7 +95,7 @@ bool GLSurface::InitializeOneOffImplementation(GLImplementation impl,
 }
 
 // static
-void GLSurface::InitializeOneOffForTests() {
+void GLSurface::InitializeOneOffForTests(bool disable_drawing) {
 #if defined(USE_X11)
   XInitThreads();
 #endif
@@ -125,7 +125,7 @@ void GLSurface::InitializeOneOffForTests() {
 
   bool fallback_to_osmesa = false;
   bool gpu_service_logging = false;
-  bool disable_gl_drawing = false;
+  bool disable_gl_drawing = disable_drawing;
   // TODO(danakj): Unit tests do not produce pixel output by default.
   // bool disable_gl_drawing = true;