Fix crash caused by concurrent access to framebuffer_combo_complete_map_.

content/common/gpu/gpu_command_buffer_stub.cc

Index: content/common/gpu/gpu_command_buffer_stub.cc
diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index c1b0127f7704b02fdd886a5d1551a32750e26f87..d410eb730ec371dd3c16b132e1a4aff8bd4d8ab9 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -209,12 +209,10 @@ GpuCommandBufferStub::GpuCommandBufferStub(
            attrib_parser.bind_generates_resource);
   } else {
     context_group_ = new gpu::gles2::ContextGroup(
-        mailbox_manager,
-        new GpuCommandBufferMemoryTracker(channel),
+        mailbox_manager, new GpuCommandBufferMemoryTracker(channel),
         channel_->gpu_channel_manager()->shader_translator_cache(),
-        NULL,
-        subscription_ref_set,
-        pending_valuebuffer_state,
+        channel_->gpu_channel_manager()->framebuffer_completeness_cache(), NULL,
+        subscription_ref_set, pending_valuebuffer_state,
         attrib_parser.bind_generates_resource);
   }