CopyTexImage2D: don't pick invalid unsized internal formats on ES3

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 1fce44cbb8d7ee858dc1d7faef634d6867c411bb..3cc5890d778af373bba4d6ef7970505c5750ad2b 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -13819,6 +13819,24 @@ void GLES2DecoderImpl::DoCopyTexImage2D(
   GLenum format =
       TextureManager::ExtractFormatFromStorageFormat(internal_format);
   GLenum type = TextureManager::ExtractTypeFromStorageFormat(internal_format);
+  bool internal_format_unsized = internal_format == format;
+  if (internal_format_unsized && feature_info_->IsWebGL2OrES3Context()) {
+    // The picks made by the temporary logic above may not be valid on ES3.
+    DCHECK(type == GL_UNSIGNED_BYTE);
+    switch (internal_format) {
+      case GL_RGB:
+      case GL_RGBA:
+      case GL_LUMINANCE_ALPHA:
+      case GL_LUMINANCE:
+      case GL_ALPHA:
+      case GL_BGRA_EXT:
+        break;
+      default:
+        // Other unsized internal_formats are invalid in ES3.

[Ken Russell (switch to Gerrit), 2016/11/10 23:32:30]

Is this correct? ES spec 3.0.5, section 3.7, table 3.3 (page 113) supports the
packed types (UNSIGNED_SHORT_4_4_4_4, UNSIGNED_SHORT_5_5_5_1,
UNSIGNED_SHORT_5_6_5) too.

[Ken Russell (switch to Gerrit), 2016/11/10 23:32:55]

Also, please refer to this table in a comment.

[Kai Ninomiya, 2016/11/10 23:50:00]

Done.

+        format = GL_NONE;
+        break;
+    }
+  }
   if (!format || !type) {
     LOCAL_SET_GL_ERROR(
         GL_INVALID_OPERATION,