Allow the renderer process to map textures from one context into another.

gpu/command_buffer/service/texture_manager.h

Index: gpu/command_buffer/service/texture_manager.h
===================================================================
--- gpu/command_buffer/service/texture_manager.h	(revision 94701)
+++ gpu/command_buffer/service/texture_manager.h	(working copy)
@@ -10,6 +10,7 @@
 #include "base/hash_tables.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "gpu/command_buffer/service/gl_utils.h"
 
 namespace gpu {
@@ -22,7 +23,7 @@
 //
 // NOTE: To support shared resources an instance of this class will need to be
 // shared by multiple GLES2Decoders.
-class TextureManager {
+class TextureManager : public base::SupportsWeakPtr<TextureManager> {
  public:
   // Info about Textures currently in the system.
   class TextureInfo : public base::RefCounted<TextureInfo> {
@@ -42,8 +43,7 @@
           cube_complete_(false),
           npot_(false),
           has_been_bound_(false),
-          framebuffer_attachment_count_(0),
-          owned_(true) {
+          framebuffer_attachment_count_(0) {
     }
 
     GLenum min_filter() const {
@@ -96,6 +96,10 @@
       return npot_;
     }
 
+    TextureManager* owner() const {
+      return owner_.get();
+    }
+
     // Returns true if mipmaps can be generated by GL.
     bool CanGenerateMipmaps(const FeatureInfo* feature_info) const;
 
@@ -128,10 +132,6 @@
       return target() && !IsDeleted();
     }
 
-    void SetNotOwned() {
-      owned_ = false;
-    }
-
     bool IsAttachedToFramebuffer() const {
       return framebuffer_attachment_count_ != 0;
     }
@@ -250,9 +250,9 @@
     // The number of framebuffers this texture is attached to.
     int framebuffer_attachment_count_;
 
-    // Whether the associated context group owns this texture and should delete
-    // it.
-    bool owned_;
+    // The framebuffer manager that controls the lifetime of this framebuffer
+    // or NULL if it has been deleted.
+    base::WeakPtr<TextureManager> owner_;
 
     DISALLOW_COPY_AND_ASSIGN(TextureInfo);
   };
@@ -338,6 +338,12 @@
   // Gets the texture info for the given texture.
   TextureInfo* GetTextureInfo(GLuint client_id);
 
+  // Adds a texture info for a texture owned by another texture
+  // manager.
+  void AddTextureInfo(const FeatureInfo* feature_info,
+                      GLuint client_id,
+                      TextureInfo* info);
+
   // Removes a texture info.
   void RemoveTextureInfo(const FeatureInfo* feature_info, GLuint client_id);