Add workaround for Mac stencil buffer leak

cc/output/in_process_context_provider.cc

Index: cc/output/in_process_context_provider.cc
diff --git a/cc/output/in_process_context_provider.cc b/cc/output/in_process_context_provider.cc
index 9fd6d182417774756ff437c68fd623d87de68394..79e7adf9fe2087017f5a854f5b89ab7a3e41ec35 100644
--- a/cc/output/in_process_context_provider.cc
+++ b/cc/output/in_process_context_provider.cc
@@ -103,7 +103,8 @@ class GrContext* InProcessContextProvider::GrContext() {
   if (gr_context_)
     return gr_context_->get();
 
-  gr_context_.reset(new skia_bindings::GrContextForGLES2Interface(ContextGL()));
+  gr_context_.reset(new skia_bindings::GrContextForGLES2Interface(
+      ContextGL(), ContextCapabilities()));
   return gr_context_->get();
 }