gpu: Add support for GLX_EXT_texture_from_pixmap extension.

gpu/command_buffer/service/context_group.h

Index: gpu/command_buffer/service/context_group.h
diff --git a/gpu/command_buffer/service/context_group.h b/gpu/command_buffer/service/context_group.h
index 671d0ffd4bfa49e0f2024bc5908105ffab850a2f..c459c568960a1086fd060118c8879ee17eaef8f5 100644
--- a/gpu/command_buffer/service/context_group.h
+++ b/gpu/command_buffer/service/context_group.h
@@ -27,6 +27,7 @@ class ProgramCache;
 class BufferManager;
 class GLES2Decoder;
 class FramebufferManager;
+class ImageManager;
 class MailboxManager;
 class RenderbufferManager;
 class ProgramManager;
@@ -43,6 +44,7 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
 
   ContextGroup(
       MailboxManager* mailbox_manager,
+      ImageManager* image_manager,
       MemoryTracker* memory_tracker,
       bool bind_generates_resource);
 
@@ -59,6 +61,10 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
     return mailbox_manager_.get();
   }
 
+  ImageManager* image_manager() const {
+    return image_manager_.get();
+  }
+
   MemoryTracker* memory_tracker() const {
     return memory_tracker_.get();
   }
@@ -149,6 +155,7 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
   bool QueryGLFeatureU(GLenum pname, GLint min_required, uint32* v);
 
   scoped_refptr<MailboxManager> mailbox_manager_;
+  scoped_refptr<ImageManager> image_manager_;
   scoped_refptr<MemoryTracker> memory_tracker_;
   scoped_ptr<TransferBufferManagerInterface> transfer_buffer_manager_;