gpu: Use explicit atomics instead of assuming that 32bit read/writes are atomic.

gpu/command_buffer/client/gles2_implementation_unittest.cc

 // 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.
 
 // Tests for GLES2Implementation.
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 
 #include <GLES2/gl2ext.h>
 #include <GLES2/gl2extchromium.h>
@@ skipping 2908 matching lines @@
   EXPECT_EQ(0, memcmp(
       &expected_end_cmds, commands, sizeof(expected_end_cmds)));
 
   // Test EndQueryEXT fails if no current query.
   ClearCommands();
   gl_->EndQueryEXT(GL_ANY_SAMPLES_PASSED_EXT);
   EXPECT_TRUE(NoCommandsWritten());
   EXPECT_EQ(GL_INVALID_OPERATION, CheckError());
 
   // Test 2nd Begin/End increments count.
-  uint32 old_submit_count = query->submit_count();
+  base::subtle::Atomic32 old_submit_count = query->submit_count();
   gl_->BeginQueryEXT(GL_ANY_SAMPLES_PASSED_EXT, id1);
   EXPECT_NE(old_submit_count, query->submit_count());
   expected_end_cmds.end_query.Init(
       GL_ANY_SAMPLES_PASSED_EXT, query->submit_count());
   commands = GetPut();
   gl_->EndQueryEXT(GL_ANY_SAMPLES_PASSED_EXT);
   EXPECT_EQ(0, memcmp(
       &expected_end_cmds, commands, sizeof(expected_end_cmds)));
 
   // Test BeginQueryEXT fails if target changed.
@@ skipping 158 matching lines @@
   Cmds expected;
   expected.cmd.Init(GL_TEXTURE_2D, mailbox.name);
   gl_->ProduceTextureCHROMIUM(GL_TEXTURE_2D, mailbox.name);
   EXPECT_EQ(0, memcmp(&expected, commands_, sizeof(expected)));
 }
 
 #include "gpu/command_buffer/client/gles2_implementation_unittest_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu