Decompress ETC texture data when there is no native support.

gpu/command_buffer/service/context_state.cc

Index: gpu/command_buffer/service/context_state.cc
diff --git a/gpu/command_buffer/service/context_state.cc b/gpu/command_buffer/service/context_state.cc
index b717c04b61c8453f196bb5d21b653ddf23c23706..8e0e341d60d36413756116a2ed4c80ca7bdc60d5 100644
--- a/gpu/command_buffer/service/context_state.cc
+++ b/gpu/command_buffer/service/context_state.cc
@@ -265,6 +265,19 @@ void ContextState::RestoreTextureUnitBindings(
   }
 }
 
+void ContextState::RestoreUnpackState() const {
+  glBindBuffer(GL_PIXEL_UNPACK_BUFFER,
+               GetBufferId(bound_pixel_unpack_buffer.get()));
+  glPixelStorei(GL_UNPACK_ALIGNMENT, unpack_alignment);
+  glPixelStorei(GL_UNPACK_SKIP_ROWS, unpack_skip_rows);
+  glPixelStorei(GL_UNPACK_SKIP_PIXELS, unpack_skip_images);
+  glPixelStorei(GL_UNPACK_SKIP_IMAGES, unpack_skip_images);

[piman, 2016/07/08 19:30:39]

We never pass GL_UNPACK_SKIP_ROWS/PIXELS/IMAGES to the driver (because we handle
them manually), so we should leave those to their default value

+
+  // UpdateUnpackParameters restores the GL_UNPACK_ROW_LENGTH and
+  // GL_UNPACK_IMAGE_HEIGHT parameters
+  UpdateUnpackParameters();
+}
+
 void ContextState::RestoreBufferBindings() const {
   if (vertex_attrib_manager.get()) {
     Buffer* element_array_buffer =