aura: Clean up compositor initialization/destruction.

components/test/run_all_unittests.cc

Index: components/test/run_all_unittests.cc
diff --git a/components/test/run_all_unittests.cc b/components/test/run_all_unittests.cc
index 49032baee6411b2c512362f8b0039e6fa14c4cfc..a881798f3959d22c7b97544f342c98f9a4bb7130 100644
--- a/components/test/run_all_unittests.cc
+++ b/components/test/run_all_unittests.cc
@@ -6,7 +6,6 @@
 #include "base/test/test_suite.h"
 #include "content/public/test/test_content_client_initializer.h"
 #include "testing/gtest/include/gtest/gtest.h"
-#include "ui/compositor/compositor_setup.h"
 
 namespace components {
 
@@ -34,9 +33,6 @@ class ComponentsUnitTestEventListener : public testing::EmptyTestEventListener {
 int main(int argc, char** argv) {
   base::TestSuite test_suite(argc, argv);
 
-  // Mock out the compositor on platforms that use it.
-  ui::SetupTestCompositor();
-
   // The listener will set up common test environment for all components unit
   // tests.
   testing::TestEventListeners& listeners =