gpu: Disable EXT_discard_framebuffer on ARM GPUs and expose it for pre-ES3

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index eea252f6181070c61863aa51e65da6b8f42d0d6d..b9fd20edcb99dcc13ab5b63a69f5e0c326b067bb 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -685,7 +685,8 @@ void FeatureInfo::InitializeFeatures() {
     // when available.
   }
 
-  if (is_es3) {
+  if ((is_es3 || extensions.Contains("GL_EXT_discard_framebuffer")) &&
+      !workarounds_.disable_ext_discard_framebuffer) {
     // DiscardFramebufferEXT is automatically bound to InvalidateFramebuffer.
     AddExtensionString("GL_EXT_discard_framebuffer");
   }