[css-typed-om] CSSUrlImageValue should set attributes to null if there was an error

As per spec[1], intrinsicWidth, intrinsicHeight, and intrinsicRatio should
return NULL , if state is other than "loaded".

[1] https://drafts.css-houdini.org/css-typed-om-1/#cssimagevalue

Bug: 792328
Change-Id: I9d3c7014136f6f2a7bd6b350ff4083389436cc54
Reviewed-on: https://chromium-review.googlesource.com/810288Reviewed-by: Darren Shen <shend@chromium.org>
Commit-Queue: Shanmuga Pandi <shanmuga.m@samsung.com>
Cr-Commit-Position: refs/heads/master@{#522346}

third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/background-image.html

@@ -9,8 +9,8 @@
 test(function() {
   testElement.attributeStyleMap.set('background-image', new CSSURLImageValue(''));
   document.body.offsetTop;
-  assert_equals(testElement.attributeStyleMap.get('background-image').intrinsicHeight, 0);
-  assert_equals(testElement.attributeStyleMap.get('background-image').intrinsicWidth, 0);
+  assert_equals(testElement.attributeStyleMap.get('background-image').intrinsicHeight, null);
+  assert_equals(testElement.attributeStyleMap.get('background-image').intrinsicWidth, null);
 }, "Check that setting background-image to CSSURLImageValue('') doesn't cause a crash");
 
 runInlineStylePropertyMapTests( {

third_party/WebKit/LayoutTests/typedcssom/stylevalue-subclasses/cssUrlImageValue-expected.txt

-This is a testharness.js-based test.
-PASS Constructing a CSSURLImageValue with an invalid URL throws a TypeError
-PASS Constructing a CSSURLImageValue with a valid URL puts it in an unloaded state
-PASS CSSURLImageValue.url is readonly
-PASS Loading a CSSURLImageValue from a URL sets its state to loaded
-PASS Loading a CSSURLImageValue from a base64 URL sets its state to loaded
-FAIL Loading a CSSURLImageValue from a URL to an invalid image sets its state to error assert_equals: expected (object) null but got (number) 0
-Harness: the test ran to completion.
-

third_party/WebKit/Source/core/css/cssom/CSSStyleImageValue.cpp

@@ -7,21 +7,21 @@
 namespace blink {
 
 double CSSStyleImageValue::intrinsicWidth(bool& is_null) const {
-  is_null = IsCachePending();
+  is_null = Status() != ResourceStatus::kCached;
   if (is_null)
     return 0;
   return ImageSize().Width();
 }
 
 double CSSStyleImageValue::intrinsicHeight(bool& is_null) const {
-  is_null = IsCachePending();
+  is_null = Status() != ResourceStatus::kCached;
   if (is_null)
     return 0;
   return ImageSize().Height();
 }
 
 double CSSStyleImageValue::intrinsicRatio(bool& is_null) {
-  is_null = IsCachePending();
+  is_null = Status() != ResourceStatus::kCached;
   if (is_null || intrinsicHeight(is_null) == 0) {
     is_null = true;
     return 0;

third_party/WebKit/Source/core/css/cssom/CSSStyleImageValueTest.cpp

@@ -22,6 +22,12 @@ class FakeCSSStyleImageValue : public CSSStyleImageValue {
   bool IsCachePending() const override { return cache_pending_; }
   IntSize ImageSize() const override { return size_; }
 
+  ResourceStatus Status() const override {
+    if (IsCachePending())
+      return ResourceStatus::kNotStarted;
+    return ResourceStatus::kCached;
+  }
+
   const CSSValue* ToCSSValue(SecureContextMode) const override {
     return nullptr;
   }