[Reland] Refactor the selection code in EventHandler

Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 4217 matching lines @@
     EXPECT_EQ(endRect, initialEndRect);
 
     moveTo.y -= 80;
     frame->moveCaretSelection(moveTo);
     webViewHelper.webView()->selectionBounds(startRect, endRect);
     EXPECT_EQ(startRect, initialStartRect);
     EXPECT_EQ(endRect, initialEndRect);
 }
 #endif
 
+TEST_F(WebFrameTest, dragSelectionAfterScroll)

[tkent, 2015/05/25 23:57:25]

Can you make EventHandlerTest.cpp or SelectionControllerTest.cpp instead of
adding a test to WebFrameTest?

[Miyoung Shin(g), 2015/05/31 14:01:13]

I made EventHandlerTest.cpp for the validation of the problem because the
problem happened after landing the patch was caused by using the wrong variable
in EventHandler.cpp.

+{
+    WebLocalFrameImpl* frame;
+    registerMockedHttpURLLoad("drag_selection.html");
+
+    FrameTestHelpers::WebViewHelper webViewHelper;
+    initializeTextSelectionWebView(m_baseURL + "drag_selection.html", &webViewHelper);
+    frame = (WebLocalFrameImpl*)webViewHelper.webView()->mainFrame();
+
+    webViewHelper.webView()->resize(WebSize(300, 400));
+    webViewHelper.webView()->layout();
+
+    // Scroll main frame to the bottom of the document
+    WebViewImpl* webViewImpl = webViewHelper.webViewImpl();
+    ASSERT_TRUE(webViewImpl);
+    webViewImpl->setMainFrameScrollOffset(WebPoint(0, 400));
+    EXPECT_POINT_EQ(IntPoint(0, 400), webViewImpl->mainFrameImpl()->frameView()->scrollPosition());
+
+    WebMouseEvent mouseDownEvent;
+    mouseDownEvent.type = WebInputEvent::MouseDown;
+    mouseDownEvent.x = 0;
+    mouseDownEvent.y = 0;
+    mouseDownEvent.windowX = 0;
+    mouseDownEvent.windowY = 0;
+    mouseDownEvent.globalX = 100;
+    mouseDownEvent.globalY = 200;
+    mouseDownEvent.clickCount = 1;
+    mouseDownEvent.button = WebMouseEvent::ButtonLeft;
+
+    WebMouseEvent mouseMoveEvent(mouseDownEvent);
+    mouseMoveEvent.type = WebInputEvent::MouseMove;
+    mouseMoveEvent.x = 100;
+    mouseMoveEvent.y = 50;
+    mouseMoveEvent.windowX = 100;
+    mouseMoveEvent.windowY = 50;
+    mouseMoveEvent.globalX = 200;
+    mouseMoveEvent.globalY = 250;
+
+    WebMouseEvent mouseUpEvent(mouseMoveEvent);
+    mouseUpEvent.type = WebInputEvent::MouseUp;
+
+    webViewHelper.webView()->handleInputEvent(mouseDownEvent);
+    webViewHelper.webView()->handleInputEvent(mouseMoveEvent);
+
+    // update the selection from beginFrame
+    WebBeginFrameArgs frameTime(0, 1, 0);
+    webViewImpl->beginFrame(frameTime);
+
+    webViewHelper.webView()->handleInputEvent(mouseUpEvent);
+
+    EXPECT_EQ("Line 1\nLine 2", selectionAsString(frame));
+}
+
 class CompositedSelectionBoundsTestLayerTreeView : public WebLayerTreeView {
 public:
     CompositedSelectionBoundsTestLayerTreeView() : m_selectionCleared(false) { }
     virtual ~CompositedSelectionBoundsTestLayerTreeView() { }
 
     virtual void setRootLayer(const WebLayer&)  override { }
     virtual void clearRootLayer()  override { }
     virtual void setViewportSize(const WebSize& deviceViewportSize)  override { }
     virtual WebSize deviceViewportSize() const  override { return WebSize(); }
     virtual void setDeviceScaleFactor(float) override { }
@@ skipping 3175 matching lines @@
 
     EXPECT_EQ(parent, firstFrame->parent());
     EXPECT_EQ(parent, secondFrame->parent());
     EXPECT_EQ(parent, thirdFrame->parent());
     EXPECT_EQ(parent, fourthFrame->parent());
 
     view->close();
 }
 
 } // namespace blink