Add a command to lose the context

gpu/command_buffer/tests/gl_test_utils.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.
 
 #include "gpu/command_buffer/tests/gl_test_utils.h"
 #include <string>
 #include <stdio.h>
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+// GCC requires these declarations, but MSVC requires they not be present.
+#ifndef COMPILER_MSVC
+const uint8 GLTestHelper::kCheckClearValue;
+#endif
+
 bool GLTestHelper::HasExtension(const char* extension) {
   std::string extensions(
       reinterpret_cast<const char*>(glGetString(GL_EXTENSIONS)));
   return extensions.find(extension) != std::string::npos;
 }
 
 bool GLTestHelper::CheckGLError(const char* msg, int line) {
    bool success = true;
    GLenum error = GL_NO_ERROR;
    while ((error = glGetError()) != GL_NO_ERROR) {
@@ skipping 78 matching lines @@
   glVertexAttribPointer(position_location, 2, GL_FLOAT, GL_FALSE, 0, 0);
 
   return vbo;
 }
 
 bool GLTestHelper::CheckPixels(
     GLint x, GLint y, GLsizei width, GLsizei height, GLint tolerance,
     const uint8* color) {
   GLsizei size = width * height * 4;
   scoped_array<uint8> pixels(new uint8[size]);
-  memset(pixels.get(), 123, size);
+  memset(pixels.get(), kCheckClearValue, size);
   glReadPixels(x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels.get());
   bool same = true;
   for (GLint yy = 0; yy < height; ++yy) {
     for (GLint xx = 0; xx < width; ++xx) {
       int offset = yy * width * 4 + xx * 4;
       for (int jj = 0; jj < 4; ++jj) {
         uint8 actual = pixels[offset + jj];
         uint8 expected = color[jj];
         int diff = actual - expected;
         diff = diff < 0 ? -diff: diff;
@@ skipping 88 matching lines @@
   fwrite(&bih, sizeof(bih), 1, fp);
   fwrite(pixels, size, 1, fp);
   fclose(fp);
   return true;
 }
 
 int GLTestHelper::RunTests(int argc, char** argv) {
   testing::InitGoogleMock(&argc, argv);
   return RUN_ALL_TESTS();
 }