FrameView can be null in addTextMatchMaker() after appendChild(iframe)

third_party/WebKit/Source/core/testing/Internals.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 1029 matching lines @@
 }
 
 void Internals::addTextMatchMarker(const Range* range, bool isActive) {
   DCHECK(range);
   range->ownerDocument().updateStyleAndLayoutIgnorePendingStylesheets();
   range->ownerDocument().markers().addTextMatchMarker(EphemeralRange(range),
                                                       isActive);
 
   // This simulates what the production code does after
   // DocumentMarkerController::addTextMatchMarker().
-  range->ownerDocument().view()->invalidatePaintForTickmarks();
+  if (range->ownerDocument().view())

[yosin_UTC9, 2017/02/21 23:24:17]

Could you do early return at top of function, e.g. L1044?
Since we don't need to update layout and update markers.

void Internals::addTextMatchMarker(const Range* range, bool isActive) {
  DCHECK(range);
  if (!range->ownerDocument().view())
   return;
  range->ownerDocument().updateStyleAndLayoutIgnorePendingStylesheets();

[hiroshige, 2017/02/21 23:29:56]

Done.

+    range->ownerDocument().view()->invalidatePaintForTickmarks();
 }
 
 static bool parseColor(const String& value,
                        Color& color,
                        ExceptionState& exceptionState,
                        String errorMessage) {
   if (!color.setFromString(value)) {
     exceptionState.throwDOMException(InvalidAccessError, errorMessage);
     return false;
   }
@@ skipping 2099 matching lines @@
 
 void Internals::crash() {
   CHECK(false) << "Intentional crash";
 }
 
 void Internals::setIsLowEndDevice(bool isLowEndDevice) {
   MemoryCoordinator::setIsLowEndDeviceForTesting(isLowEndDevice);
 }
 
 }  // namespace blink