Simplify "WouldTaintOrigin" concept in media/blink

Currently WebMediaPlayer has three predicates:
 - DidGetOpaqueResponseFromServiceWorker
 - HasSingleSecurityOrigin
 - DidPassCORSAccessCheck
. These are used to determine whether the response body is available
for scripts. They are known to be confusing, and actually
MediaElementAudioSourceHandler::WouldTaintOrigin misuses them.

This CL merges the three predicates to one, WouldTaintOrigin, to remove
the confusion. Now the "response type" concept is available and we
don't need a custom CORS check, so this CL removes
BaseAudioContext::WouldTaintOrigin. This CL also renames
URLData::has_opaque_data_ and its (direct and indirect) data accessors
to match the spec.

Bug: 849942, 875153
Change-Id: I6acf50169d7445c4ff614e80ac606f79ee577d2a
Reviewed-on: https://chromium-review.googlesource.com/c/1238098
Reviewed-by: Fredrik Hubinette <hubbe@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Raymond Toy <rtoy@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#598258}
void HTMLMediaElement::NoneSupported(const String& input_message) {
  BLINK_MEDIA_LOG << "NoneSupported(" << (void*)this << ", message='"
                  << input_message << "')";

  StopPeriodicTimers();
  load_state_ = kWaitingForSource;
  current_source_node_ = nullptr;

  String empty_string;
  const String& message = MediaShouldBeOpaque() ? empty_string : input_message;


  error_ = MediaError::Create(MediaError::kMediaErrSrcNotSupported, message);

  ForgetResourceSpecificTracks();

  SetNetworkState(kNetworkNoSource);

  UpdateDisplayState();

  ScheduleEvent(EventTypeNames::error);

  ScheduleRejectPlayPromises(DOMExceptionCode::kNotSupportedError);

  CloseMediaSource();

  SetShouldDelayLoadEvent(false);

  if (GetLayoutObject())
    GetLayoutObject()->UpdateFromElement();
}

void HTMLMediaElement::NoneSupported(const String& input_message) {
  BLINK_MEDIA_LOG << "NoneSupported(" << (void*)this << ", message='"
                  << input_message << "')";

  StopPeriodicTimers();
  load_state_ = kWaitingForSource;
  current_source_node_ = nullptr;

  String empty_string;
  const String& message = MediaShouldBeOpaque() ? empty_string : input_message;


  error_ = MediaError::Create(MediaError::kMediaErrSrcNotSupported, message);

  ForgetResourceSpecificTracks();

  SetNetworkState(kNetworkNoSource);

  UpdateDisplayState();

  ScheduleEvent(EventTypeNames::error);

  ScheduleRejectPlayPromises(DOMExceptionCode::kNotSupportedError);

  CloseMediaSource();

  SetShouldDelayLoadEvent(false);

  if (GetLayoutObject())
    GetLayoutObject()->UpdateFromElement();
}
