Do not send redundant selectionchange-events (decouple focus)

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 a9b73309056902de3f12819f47739c725b990ebf..a4a760a5a0b6d70e1866d274819e7d07fa34e0ad 100644
--- a/third_party/WebKit/Source/web/tests/WebFrameTest.cpp
+++ b/third_party/WebKit/Source/web/tests/WebFrameTest.cpp
@@ -4237,6 +4237,52 @@ TEST_P(ParameterizedWebFrameTest, ClearFocusedNodeTest) {
   EXPECT_EQ(0, webViewHelper.webView()->focusedElement());
 }
 
+class ChangedSelectionCounter : public FrameTestHelpers::TestWebFrameClient {
+ public:
+  ChangedSelectionCounter() : m_callCount(0) {}
+  void didChangeSelection(bool isSelectionEmpty) { m_callCount++; }

[yosin_UTC9, 2017/02/09 13:02:17]

nit: It is OK to use post-increment, but I prefer pre-increment as same as
iterator increment pattern.

+  int count() const { return m_callCount; }
+  void reset() { m_callCount = 0; }
+
+ private:
+  int m_callCount;
+};
+
+TEST_P(ParameterizedWebFrameTest, OneFocusChangeMeansOneSelectionChange) {
+  ChangedSelectionCounter counter;
+  FrameTestHelpers::WebViewHelper webViewHelper;
+  registerMockedHttpURLLoad("editable_elements.html");
+  webViewHelper.initializeAndLoad(m_baseURL + "editable_elements.html", true,
+                                  &counter);
+
+  WebLocalFrameImpl* frame = webViewHelper.webView()->mainFrameImpl();
+  Document* document = frame->frame()->document();
+
+  // Move to a text-field.
+  Element* firstField = document->getElementById("input1");
+  counter.reset();
+  firstField->focus();
+  EXPECT_EQ(1, counter.count());
+
+  // Move to another text-field.
+  Element* secondField = document->getElementById("input2");
+  counter.reset();
+  secondField->focus();
+  EXPECT_EQ(1, counter.count());
+
+  // Move to a number-field.
+  Element* numberField = document->getElementById("input3");
+  counter.reset();
+  numberField->focus();
+  EXPECT_EQ(1, counter.count());
+
+  // Move to an editable element.
+  Element* editableP = document->getElementById("p1");
+  counter.reset();
+  editableP->focus();
+  EXPECT_EQ(1, counter.count());
+}
+
 // Implementation of WebFrameClient that tracks the v8 contexts that are created
 // and destroyed for verification.
 class ContextLifetimeTestWebFrameClient