[content shell] Do not disable cc-driven animation when using threaded compositing

content/shell/app/shell_main_delegate.cc

Index: content/shell/app/shell_main_delegate.cc
diff --git a/content/shell/app/shell_main_delegate.cc b/content/shell/app/shell_main_delegate.cc
index e21a0cfb5f8c11bf67abe76311a6428fa0088b4c..386986245b3a5b6139e714dd7e7e94f0b0933eae 100644
--- a/content/shell/app/shell_main_delegate.cc
+++ b/content/shell/app/shell_main_delegate.cc
@@ -125,7 +125,8 @@ bool ShellMainDelegate::BasicStartupComplete(int* exit_code) {
     command_line.AppendSwitchASCII(switches::kTouchEvents,
                                    switches::kTouchEventsEnabled);
     command_line.AppendSwitch(switches::kEnableGestureTapHighlight);
-    command_line.AppendSwitch(cc::switches::kDisableThreadedAnimation);
+    if (!command_line.HasSwitch(switches::kEnableThreadedCompositing))
+      command_line.AppendSwitch(cc::switches::kDisableThreadedAnimation);
     if (command_line.HasSwitch(switches::kEnableSoftwareCompositing))
       command_line.AppendSwitch(switches::kEnableSoftwareCompositingGLAdapter);