Remove callOnMainThread

sky/engine/testing/platform/platform_impl.cc

Index: sky/engine/testing/platform/platform_impl.cc
diff --git a/sky/engine/testing/platform/platform_impl.cc b/sky/engine/testing/platform/platform_impl.cc
index 683f864501804c9b290f320e8aa28178682f2e41..238480db4956064e72b69a431dfbc142ef17ee30 100644
--- a/sky/engine/testing/platform/platform_impl.cc
+++ b/sky/engine/testing/platform/platform_impl.cc
@@ -86,11 +86,6 @@ void PlatformImpl::stopSharedTimer() {
   shared_timer_.Stop();
 }
 
-void PlatformImpl::callOnMainThread(
-    void (*func)(void*), void* context) {
-  main_loop_->PostTask(FROM_HERE, base::Bind(func, context));
-}
-
 blink::WebUnitTestSupport* PlatformImpl::unitTestSupport() {
   return &unit_test_support_;
 }