Revert of gpu: fix CopyTextureCHROMIUM for immutable texture. (patchset #4 id:60001 of https://codereview.chromium.org/744713002/)

Reason for revert:
Broke video uploads to WebGL on official builds (taking the hardware accelerated video decode path). See Issue 436538.

Original issue's description:
> gpu: fix CopyTextureCHROMIUM for immutable texture.
>
> We cannot use glCopyTexImage2D on the texture which is allocated by glTexStorage2D [1]
> [1] https://www.opengl.org/registry/specs/ARB/texture_storage.txt
> The fast path uses glCopyTexSubImage2D instead of glCopyTexImage2D.
>
> In addition, optimize CopyTextureCHROMIUM for GL_TEXTURE_RECTANGLE_ARB,
> which is often used by the compositor, so make CopyTextureCHROMIUM use
> the fast path.
>
> Committed: https://crrev.com/df36f0aebe453bdbe842c85b331f6f07a24255a2
> Cr-Commit-Position: refs/heads/master@{#305268}

TBR=sievers@chromium.org,reveman@chromium.org,dongseong.hwang@intel.com
BUG=436538

Review URL: https://codereview.chromium.org/760173002

Cr-Commit-Position: refs/heads/master@{#305937}

2 files changed, 13 insertions, 42 deletions

diff --git a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
index 49bba9b..ffb9370 100644
--- a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
+++ b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
@@ -218,6 +218,7 @@ void DoCopyTexImage2D(const gpu::gles2::GLES2Decoder* decoder,
                       GLuint source_id,
                       GLuint dest_id,
                       GLint dest_level,
+                      GLenum dest_internal_format,
                       GLsizei width,
                       GLsizei height,
                       GLuint framebuffer) {
@@ -230,8 +231,14 @@ void DoCopyTexImage2D(const gpu::gles2::GLES2Decoder* decoder,
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glCopyTexSubImage2D(GL_TEXTURE_2D, dest_level, 0 /* xoffset */,
-                        0 /* yoffset */, 0 /* x */, 0 /* y */, width, height);
+    glCopyTexImage2D(GL_TEXTURE_2D,
+                     dest_level,
+                     dest_internal_format,
+                     0 /* x */,
+                     0 /* y */,
+                     width,
+                     height,
+                     0 /* border */);
   }
 
   decoder->RestoreTextureState(source_id);
@@ -325,15 +332,16 @@ void CopyTextureCHROMIUMResourceManager::DoCopyTexture(
   bool source_format_contain_superset_of_dest_format =
       source_internal_format == dest_internal_format ||
       (source_internal_format == GL_RGBA && dest_internal_format == GL_RGB);
-  bool source_target_allowed = source_target == GL_TEXTURE_2D ||
-                               source_target == GL_TEXTURE_RECTANGLE_ARB;
-  if (source_target_allowed && !flip_y && !premultiply_alpha_change &&
+  // GL_TEXTURE_RECTANGLE_ARB on FBO is supported by OpenGL, not GLES2,
+  // so restrict this to GL_TEXTURE_2D.
+  if (source_target == GL_TEXTURE_2D && !flip_y && !premultiply_alpha_change &&
       source_format_contain_superset_of_dest_format) {
     DoCopyTexImage2D(decoder,
                      source_target,
                      source_id,
                      dest_id,
                      dest_level,
+                     dest_internal_format,
                      width,
                      height,
                      framebuffer_);
diff --git a/gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc b/gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc
index a8cbb66..2c44e1a 100644
--- a/gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc
+++ b/gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc
@@ -76,43 +76,6 @@ TEST_F(GLCopyTextureCHROMIUMTest, Basic) {
   EXPECT_TRUE(GL_NO_ERROR == glGetError());
 }
 
-TEST_F(GLCopyTextureCHROMIUMTest, ImmutableTexture) {
-  if (!GLTestHelper::HasExtension("GL_EXT_texture_storage")) {
-    LOG(INFO) << "GL_EXT_texture_storage not supported. Skipping test...";
-    return;
-  }
-
-  uint8 pixels[1 * 4] = {255u, 0u, 0u, 255u};
-
-  glBindTexture(GL_TEXTURE_2D, textures_[0]);
-  glTexStorage2DEXT(GL_TEXTURE_2D, 1, GL_RGBA8_OES, 1, 1);
-  glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE,
-                  pixels);
-
-  glBindTexture(GL_TEXTURE_2D, textures_[1]);
-  glTexStorage2DEXT(GL_TEXTURE_2D, 1, GL_RGBA8_OES, 1, 1);
-  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
-                         textures_[1], 0);
-  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
-
-  glCopyTextureCHROMIUM(GL_TEXTURE_2D, textures_[0], textures_[1], 0, GL_RGBA,
-                        GL_UNSIGNED_BYTE);
-  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
-
-  // Check the FB is still bound.
-  GLint value = 0;
-  glGetIntegerv(GL_FRAMEBUFFER_BINDING, &value);
-  GLuint fb_id = value;
-  EXPECT_EQ(framebuffer_id_, fb_id);
-
-  // Check that FB is complete.
-  EXPECT_EQ(static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE),
-            glCheckFramebufferStatus(GL_FRAMEBUFFER));
-
-  GLTestHelper::CheckPixels(0, 0, 1, 1, 0, pixels);
-  EXPECT_TRUE(GL_NO_ERROR == glGetError());
-}
-
 TEST_F(GLCopyTextureCHROMIUMTest, InternalFormat) {
   GLint src_formats[] = {GL_ALPHA,     GL_RGB,             GL_RGBA,
                          GL_LUMINANCE, GL_LUMINANCE_ALPHA, GL_BGRA_EXT};