Fix the problem to keep the selection when clicking the substring out of range

Source/core/page/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 542 matching lines @@
                 else
                     newSelection = VisibleSelection(start, pos);
             }
         } else
             newSelection.setExtent(pos);
 
         if (m_frame->selection().granularity() != CharacterGranularity) {
             granularity = m_frame->selection().granularity();
             newSelection.expandUsingGranularity(m_frame->selection().granularity());
         }
-    } else {
+    } else if (m_selectionInitiationState != ExtendedSelection) {

[Donn Denman, 2014/12/09 00:59:37]

This line causes a problem for Contextual Search (a feature for Chrome on
Android).

         newSelection = expandSelectionToRespectUserSelectAll(innerNode, VisibleSelection(visiblePos));
     }
 
     // Updating the selection is considered side-effect of the event and so it doesn't impact the handled state.
     updateSelectionForMouseDownDispatchingSelectStart(innerNode, newSelection, granularity);
     return false;
 }
 
 static inline bool canMouseDownStartSelect(Node* node)
 {
@@ skipping 2405 matching lines @@
 void EventHandler::notifyElementActivated()
 {
     // Since another element has been set to active, stop current timer and clear reference.
     if (m_activeIntervalTimer.isActive())
         m_activeIntervalTimer.stop();
     m_lastDeferredTapElement = nullptr;
 }
 
 void EventHandler::notifySelectionChanged()
 {
-    m_selectionInitiationState = ExtendedSelection;
+    if (m_frame->selection().isRange())
+        m_selectionInitiationState = ExtendedSelection;
 }
 
 bool EventHandler::handleAccessKey(const PlatformKeyboardEvent& evt)
 {
     // FIXME: Ignoring the state of Shift key is what neither IE nor Firefox do.
     // IE matches lower and upper case access keys regardless of Shift key state - but if both upper and
     // lower case variants are present in a document, the correct element is matched based on Shift key state.
     // Firefox only matches an access key if Shift is not pressed, and does that case-insensitively.
     ASSERT(!(accessKeyModifiers() & PlatformEvent::ShiftKey));
     if ((evt.modifiers() & ~PlatformEvent::ShiftKey) != accessKeyModifiers())
@@ skipping 863 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace blink