Use a mocked compositor for unit tests

views/run_all_unittests.cc

Index: views/run_all_unittests.cc
diff --git a/views/run_all_unittests.cc b/views/run_all_unittests.cc
index 90fd4dda1307d6c72bff14705c284856a692c29c..84012e08853215aa46a55ca5f6bdf50109ddb03d 100644
--- a/views/run_all_unittests.cc
+++ b/views/run_all_unittests.cc
@@ -7,6 +7,16 @@
 #include "ui/base/ui_base_paths.h"
 #include "views/view.h"
 
+#if defined(OS_LINUX)
+#include "base/command_line.h"
+#include "ui/gfx/gl/gl_switches.h"
+#endif
+
+#if defined(VIEWS_COMPOSITOR)
+#include "ui/gfx/compositor/compositor.h"
+#include "ui/gfx/compositor/test_compositor.h"
+#endif
+
 class ViewTestSuite : public base::TestSuite {
  public:
   ViewTestSuite(int argc, char** argv) : base::TestSuite(argc, argv) {}
@@ -19,8 +29,15 @@ class ViewTestSuite : public base::TestSuite {
     ui::ResourceBundle::InitSharedInstance("en-US");
 
 #if defined(OS_LINUX)
-    // Disable GPU browser compositor during unit tests.
-    views::View::set_use_acceleration_when_possible(false);
+    EXPECT_TRUE(!CommandLine::ForCurrentProcess()->HasSwitch(switches::kUseGL));
+    CommandLine::ForCurrentProcess()->AppendSwitchASCII(
+        switches::kUseGL, gfx::kGLImplementationOSMesaName);
+#endif
+
+#if defined(VIEWS_COMPOSITOR)
+   // Use a mock compositor that noops draws.
+    ui::Compositor::set_compositor_factory_for_testing(
+        ui::TestCompositor::Create);
 #endif
   }
 };