Add a command to lose the context

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 c459c568960a1086fd060118c8879ee17eaef8f5..064e36f3fdeea25b46071f8d4c67723383bf3e76 100644
--- a/gpu/command_buffer/service/context_group.h
+++ b/gpu/command_buffer/service/context_group.h
@@ -6,11 +6,13 @@
 #define GPU_COMMAND_BUFFER_SERVICE_CONTEXT_GROUP_H_
 
 #include <string>
+#include <vector>
 #include "base/basictypes.h"
 #include "base/hash_tables.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "gpu/command_buffer/common/gles2_cmd_format.h"
 #include "gpu/command_buffer/service/gles2_cmd_validation.h"
 #include "gpu/command_buffer/service/feature_info.h"
@@ -50,12 +52,14 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
 
   // This should only be called by GLES2Decoder. This must be paired with a
   // call to destroy if it succeeds.
-  bool Initialize(const DisallowedFeatures& disallowed_features,
-                  const char* allowed_features);
+  bool Initialize(
+      GLES2Decoder* decoder,
+      const DisallowedFeatures& disallowed_features,
+      const char* allowed_features);
 
   // Destroys all the resources when called for the last context in the group.
   // It should only be called by GLES2Decoder.
-  void Destroy(bool have_context);
+  void Destroy(GLES2Decoder* decoder, bool have_context);
 
   MailboxManager* mailbox_manager() const {
     return mailbox_manager_.get();
@@ -145,6 +149,9 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
 
   uint32 GetMemRepresented() const;
 
+  // Loses all the context associated with this group.
+  void LoseContexts(GLenum reset_status);
+
  private:
   friend class base::RefCounted<ContextGroup>;
   ~ContextGroup();
@@ -153,14 +160,13 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
   bool CheckGLFeatureU(GLint min_required, uint32* v);
   bool QueryGLFeature(GLenum pname, GLint min_required, GLint* v);
   bool QueryGLFeatureU(GLenum pname, GLint min_required, uint32* v);
+  bool HaveContexts();
 
   scoped_refptr<MailboxManager> mailbox_manager_;
   scoped_refptr<ImageManager> image_manager_;
   scoped_refptr<MemoryTracker> memory_tracker_;
   scoped_ptr<TransferBufferManagerInterface> transfer_buffer_manager_;
 
-  // Whether or not this context is initialized.
-  int num_contexts_;
   bool enforce_gl_minimums_;
   bool bind_generates_resource_;
 
@@ -191,6 +197,8 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
 
   FeatureInfo::Ref feature_info_;
 
+  std::vector<base::WeakPtr<gles2::GLES2Decoder> > decoders_;
+
   DISALLOW_COPY_AND_ASSIGN(ContextGroup);
 };