Fixed tough texture upload benchmark on low end devices.

gpu/command_buffer/client/gles2_implementation.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_
 #define GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_
 
 #include <list>
 #include <map>
 #include <queue>
@@ skipping 728 matching lines @@
 
   // When true, the context is lost when a GL_OUT_OF_MEMORY error occurs.
   const bool lose_context_when_out_of_memory_;
 
   // Whether or not to support client side arrays.
   const bool support_client_side_arrays_;
 
   // Used to check for single threaded access.
   int use_count_;
 
+  // Maximum amount of extra shared memory to use when needing to transfer

[no sievers, 2015/10/19 15:55:04]

nit: maybe say 'extra memory from the mapped memory pool', since it's
technically not entirely 'extra' but part of an existing pool

[David Yen, 2015/10/19 16:02:18]

Done.

+  // something exceeding the default transfer buffer. This should be 0 for
+  // low memory devices since they are already memory constrained.
+  const uint32_t max_extra_transfer_buffer_size_;
+
   // Map of GLenum to Strings for glGetString.  We need to cache these because
   // the pointer passed back to the client has to remain valid for eternity.
   typedef std::map<uint32, std::set<std::string> > GLStringMap;
   GLStringMap gl_strings_;
 
   // Similar cache for glGetRequestableExtensionsCHROMIUM. We don't
   // have an enum for this so handle it separately.
   std::set<std::string> requestable_extensions_set_;
 
   typedef std::map<const void*, MappedBuffer> MappedBufferMap;
@@ skipping 68 matching lines @@
 
 inline bool GLES2Implementation::GetTexParameterivHelper(
     GLenum /* target */, GLenum /* pname */, GLint* /* params */) {
   return false;
 }
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_