StreamTextureImages can now override a Texture's service id

gpu/command_buffer/service/texture_manager.h

Index: gpu/command_buffer/service/texture_manager.h
diff --git a/gpu/command_buffer/service/texture_manager.h b/gpu/command_buffer/service/texture_manager.h
index 5d1a518236207dd29326431762976fca8e4101a4..347116ea5662eac131f6c91bf5a51d1aa5278e43 100644
--- a/gpu/command_buffer/service/texture_manager.h
+++ b/gpu/command_buffer/service/texture_manager.h
@@ -156,7 +156,9 @@ class GPU_EXPORT Texture {
   // Causes us to report |service_id| as our service id, but does not delete
   // it when we are destroyed.  Will rebind any OES_EXTERNAL texture units to
   // our new service id in all contexts.  If |service_id| is zero, then we
-  // revert to our original service id.
+  // revert to our original service id. The unowned service id is automatically
+  // reset whenever an image is bound to this Texture to ensure the unowned id
+  // doesn't outlive the image that owns it.
   void SetUnownedServiceId(GLuint service_id);
 
   // Returns the target this texure was first bound to or 0 if it has not