Add generated and hand-written passthrough command handlers with stub Doers.

gpu/command_buffer/common/gles2_cmd_utils.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.
 
 // This file is here so other GLES2 related files can have a common set of
 // includes where appropriate.
 
 #ifndef GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_
 #define GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_
 
@@ skipping 35 matching lines @@
 
 // Does an add checking for overflow.  If there was no overflow returns true.
 inline bool SafeAddInt32(int32_t a, int32_t b, int32_t* dst) {
   DCHECK(dst);
   base::CheckedNumeric<int32_t> checked = a;
   checked += b;
   *dst = checked.ValueOrDefault(0);
   return checked.IsValid();
 }
 
+// Returns the address of the first byte after a struct.
+template <typename T>
+const void* AddressAfterStruct(const T& pod) {
+  return reinterpret_cast<const uint8_t*>(&pod) + sizeof(pod);
+}
+
+// Returns the address of the frst byte after the struct or NULL if size >

[piman, 2016/05/25 23:34:42]

nit: frst->first

+// immediate_data_size.
+template <typename RETURN_TYPE, typename COMMAND_TYPE>
+RETURN_TYPE GetImmediateDataAs(const COMMAND_TYPE& pod,
+                               uint32_t size,
+                               uint32_t immediate_data_size) {
+  return (size <= immediate_data_size)
+             ? static_cast<RETURN_TYPE>(
+                   const_cast<void*>(AddressAfterStruct(pod)))
+             : NULL;
+}
+
 struct GLES2_UTILS_EXPORT PixelStoreParams {
   PixelStoreParams()
       : alignment(4),
         row_length(0),
         image_height(0),
         skip_pixels(0),
         skip_rows(0),
         skip_images(0) {
   }
 
@@ skipping 232 matching lines @@
   bool fail_if_major_perf_caveat;
   bool lose_context_when_out_of_memory;
   ContextType context_type;
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_