Add optimization for CHROMIUM_subscribe_uniform extension.

content/common/gpu/gpu_channel.cc

Index: content/common/gpu/gpu_channel.cc
diff --git a/content/common/gpu/gpu_channel.cc b/content/common/gpu/gpu_channel.cc
index 7bf61344c8fb2029e179fd21b2a92e5a9219f7c6..d15c89c7591c9719e7ea52c9fe977a2e27b5bce7 100644
--- a/content/common/gpu/gpu_channel.cc
+++ b/content/common/gpu/gpu_channel.cc
@@ -29,6 +29,7 @@
 #include "gpu/command_buffer/service/image_factory.h"
 #include "gpu/command_buffer/service/mailbox_manager_impl.h"
 #include "gpu/command_buffer/service/sync_point_manager.h"
+#include "gpu/command_buffer/service/valuebuffer_manager.h"
 #include "ipc/ipc_channel.h"
 #include "ipc/message_filter.h"
 #include "ui/gl/gl_context.h"
@@ -403,6 +404,7 @@ GpuChannel::GpuChannel(GpuChannelManager* gpu_channel_manager,
                        GpuWatchdog* watchdog,
                        gfx::GLShareGroup* share_group,
                        gpu::gles2::MailboxManager* mailbox,
+                       gpu::gles2::SubscriptionRefSet* subscription_ref_set,
                        int client_id,
                        bool software,
                        bool allow_future_sync_points)
@@ -411,6 +413,7 @@ GpuChannel::GpuChannel(GpuChannelManager* gpu_channel_manager,
       client_id_(client_id),
       share_group_(share_group ? share_group : new gfx::GLShareGroup),
       mailbox_manager_(mailbox ? mailbox : new gpu::gles2::MailboxManagerImpl),
+      subscription_ref_set_(subscription_ref_set),
       watchdog_(watchdog),
       software_(software),
       handle_messages_scheduled_(false),
@@ -581,6 +584,7 @@ CreateCommandBufferResult GpuChannel::CreateViewCommandBuffer(
                                share_group,
                                window,
                                mailbox_manager_.get(),
+                               subscription_ref_set_.get(),
                                pending_valuebuffer_state_.get(),
                                gfx::Size(),
                                disallowed_features_,
@@ -740,6 +744,7 @@ void GpuChannel::OnCreateOffscreenCommandBuffer(
       share_group,
       gfx::GLSurfaceHandle(),
       mailbox_manager_.get(),
+      subscription_ref_set_.get(),
       pending_valuebuffer_state_.get(),
       size,
       disallowed_features_,