gpu: Make CopyTexture work with GL_BGRA_EXT destination textures.

gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_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.
 
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES
 #endif
 
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
@@ skipping 98 matching lines @@
 }
 
 TEST_F(GLCopyTextureCHROMIUMTest, InternalFormatNotSupported) {
   glBindTexture(GL_TEXTURE_2D, textures_[0]);
   glTexImage2D(
       GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
   EXPECT_TRUE(GL_NO_ERROR == glGetError());
 
   // Check unsupported format reports error.
   GLint unsupported_dest_formats[] = {GL_ALPHA, GL_LUMINANCE,
-                                      GL_LUMINANCE_ALPHA, GL_BGRA_EXT};
+                                      GL_LUMINANCE_ALPHA};
   for (size_t dest_index = 0; dest_index < arraysize(unsupported_dest_formats);
        dest_index++) {
     glCopyTextureCHROMIUM(GL_TEXTURE_2D,
                           textures_[0],
                           textures_[1],
                           0,
                           unsupported_dest_formats[dest_index],
                           GL_UNSIGNED_BYTE);
     EXPECT_TRUE(GL_INVALID_OPERATION == glGetError())
         << "dest_index:" << dest_index;
@@ skipping 493 matching lines @@
       EXPECT_EQ(0, pixels[y][x][1]);
       EXPECT_EQ(0, pixels[y][x][2]);
       EXPECT_EQ(0, pixels[y][x][3]);
     }
   }
 
   EXPECT_TRUE(GL_NO_ERROR == glGetError());
 }
 
 }  // namespace gpu