Consider empty url case when loading image

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

Index: third_party/WebKit/Source/web/tests/WebFrameTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/WebFrameTest.cpp b/third_party/WebKit/Source/web/tests/WebFrameTest.cpp
index 0cc79443ce04832706b604e4c999995648191ddb..35b4b542f726932598fa54726878053a3049939a 100644
--- a/third_party/WebKit/Source/web/tests/WebFrameTest.cpp
+++ b/third_party/WebKit/Source/web/tests/WebFrameTest.cpp
@@ -12153,4 +12153,29 @@ TEST_F(WebFrameTest, FallbackForNonexistentProvisionalNavigation) {
             child->MaybeRenderFallbackContent(WebURLError()));
 }
 
+TEST_F(WebFrameTest, AltTextOnAboutBlankPage) {
+  FrameTestHelpers::WebViewHelper web_view_helper;
+  web_view_helper.InitializeAndLoad("about:blank", true);
+  web_view_helper.Resize(WebSize(640, 480));
+  WebLocalFrameImpl* frame = web_view_helper.WebView()->MainFrameImpl();
+
+  const char kSource[] =
+      "<img src='foo' alt='foo alt' width='200' height='200'>";

[Nate Chapin, 2017/05/17 17:53:50]

Add id='i' to this...

+  FrameTestHelpers::LoadHTMLString(frame, kSource, ToKURL("about:blank"));
+  web_view_helper.WebView()->UpdateAllLifecyclePhases();
+  RunPendingTasks();
+
+  // Check LayoutText with alt text "foo alt"
+  LayoutObject* root = frame->GetFrame()->ContentLayoutObject();
+  String text = "";
+  for (LayoutObject* obj = root; obj; obj = obj->NextInPreOrder()) {

[Nate Chapin, 2017/05/17 17:53:50]

If I understood dmazzoni's comment correctly, if you add the id to the img tag,
you should be able to do:

LayoutText* layout_text =
ToLayoutText(frame->GetFrame()->GetDocument()->GetElementById("i")->GetLayoutObject()->SlowFirstChild());

..which would avoid the loop.

+    if (obj->IsText()) {
+      LayoutText* layout_text = ToLayoutText(obj);
+      text = layout_text->GetText();
+      break;
+    }
+  }
+  EXPECT_EQ("foo alt", text.Utf8());
+}
+
 }  // namespace blink