Shape Detection: resolve with empty results if any input element's dimension is zero

third_party/WebKit/Source/modules/shapedetection/ShapeDetector.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "modules/shapedetection/ShapeDetector.h"
 
 #include "core/dom/DOMException.h"
 #include "core/dom/DOMRect.h"
 #include "core/dom/Document.h"
 #include "core/frame/ImageBitmap.h"
@@ skipping 89 matching lines @@
                        canvasImageSource->sourceHeight());
 
   SourceImageStatus sourceImageStatus = InvalidSourceImageStatus;
   RefPtr<Image> image = canvasImageSource->getSourceImageForCanvas(
       &sourceImageStatus, PreferNoAcceleration, SnapshotReasonDrawImage, size);
   if (!image || sourceImageStatus != NormalSourceImageStatus) {
     resolver->reject(
         DOMException::create(InvalidStateError, "Invalid element or state."));
     return promise;
   }
+  if (size.isEmpty()) {
+    resolver->resolve(HeapVector<Member<DOMRect>>());
+    return promise;
+  }
 
   SkPixmap pixmap;
   RefPtr<Uint8Array> pixelData;
   uint8_t* pixelDataPtr = nullptr;
   WTF::CheckedNumeric<int> allocationSize = 0;
 
   // TODO(ccameron): ShapeDetector can ignore color conversion.
   sk_sp<SkImage> skImage =
       image->imageForCurrentFrame(ColorBehavior::transformToGlobalTarget());
   // Use |skImage|'s pixels if it has direct access to them.
@@ skipping 23 matching lines @@
 
   return doDetect(resolver, std::move(sharedBufferHandle), image->width(),
                   image->height());
 }
 
 ScriptPromise ShapeDetector::detectShapesOnImageData(
     ScriptPromiseResolver* resolver,
     ImageData* imageData) {
   ScriptPromise promise = resolver->promise();
 
+  if (imageData->size().isZero()) {
+    resolver->resolve(HeapVector<Member<DOMRect>>());
+    return promise;
+  }
+
   uint8_t* const data = imageData->data()->data();
   WTF::CheckedNumeric<int> allocationSize = imageData->size().area() * 4;
 
   mojo::ScopedSharedBufferHandle sharedBufferHandle =
       getSharedBufferOnData(resolver, data, allocationSize.ValueOrDefault(0));
   if (!sharedBufferHandle->is_valid())
     return promise;
 
   return doDetect(resolver, std::move(sharedBufferHandle), imageData->width(),
                   imageData->height());
 }
 
 ScriptPromise ShapeDetector::detectShapesOnImageElement(
     ScriptPromiseResolver* resolver,
     const HTMLImageElement* img) {
   ScriptPromise promise = resolver->promise();
 
-  // TODO(mcasas): reconsider this resolve(), https://crbug.com/674306.
   if (img->bitmapSourceSize().isZero()) {
     resolver->resolve(HeapVector<Member<DOMRect>>());
     return promise;
   }
 
   ImageResourceContent* const imageResource = img->cachedImage();
   if (!imageResource || imageResource->errorOccurred()) {
     resolver->reject(DOMException::create(
         InvalidStateError, "Failed to load or decode HTMLImageElement."));
     return promise;
@@ skipping 45 matching lines @@
         InvalidStateError,
         "Failed to read pixels: Unable to decompress or unsupported format."));
     return promise;
   }
 
   return doDetect(resolver, std::move(sharedBufferHandle), img->naturalWidth(),
                   img->naturalHeight());
 }
 
 }  // namespace blink