Add video frame information to "unsupported frame type" error.

This is necessary to help debugging efforts.

R=tguilbert

Bug: 1148800
Change-Id: If638329d288701b1a95e7215935a4cf424dafcc3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2542048
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Auto-Submit: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827963}

third_party/blink/renderer/modules/webcodecs/video_frame.cc

@@ -503,8 +503,10 @@ ScriptPromise VideoFrame::CreateImageBitmap(ScriptState* script_state,
                                                  exception_state);
   }
 
-  exception_state.ThrowDOMException(DOMExceptionCode::kNotSupportedError,
-                                    "Unsupported VideoFrame.");
+  exception_state.ThrowDOMException(
+      DOMExceptionCode::kNotSupportedError,
+      String(("Unsupported VideoFrame: " + local_frame->AsHumanReadableString())
+                 .c_str()));
   return ScriptPromise();
 }