Reland of Extend CopyTextureCHROMIUM to more ES 3.0 texture formats.

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 <GLES2/gl2extchromium.h>
 #include <stdint.h>
 #include <stdio.h>
 
@@ skipping 191 matching lines @@
   glVertexAttribPointer(location, 4, GL_FLOAT, GL_FALSE, 0, 0);
 
   return vbo;
 }
 
 bool GLTestHelper::CheckPixels(GLint x,
                                GLint y,
                                GLsizei width,
                                GLsizei height,
                                GLint tolerance,
-                               const uint8_t* color) {
+                               const uint8_t* color,
+                               int channel_count) {
   GLsizei size = width * height * 4;
   std::unique_ptr<uint8_t[]> pixels(new uint8_t[size]);
   memset(pixels.get(), kCheckClearValue, size);
   glReadPixels(x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels.get());
   int bad_count = 0;
+  channel_count = channel_count > 4 ? 4 : channel_count;
   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) {
+      for (int jj = 0; jj < channel_count; ++jj) {
         uint8_t actual = pixels[offset + jj];
         uint8_t expected = color[jj];
         int diff = actual - expected;
         diff = diff < 0 ? -diff: diff;
         if (diff > tolerance) {
           EXPECT_EQ(expected, actual) << " at " << (xx + x) << ", " << (yy + y)
                                       << " channel " << jj;
           ++bad_count;
           // Exit early just so we don't spam the log but we print enough
           // to hopefully make it easy to diagnose the issue.
@@ skipping 119 matching lines @@
   ASSERT_NE(vertex_buffer, 0u);
   glUniform1i(sampler_location, 0);
 
   glDrawArrays(GL_TRIANGLES, 0, 6);
 
   glDeleteShader(vertex_shader);
   glDeleteShader(fragment_shader);
   glDeleteProgram(program);
   glDeleteBuffers(1, &vertex_buffer);
 }