Use focused RenderWidgetHostImpl instead of TextInputManager::GetActiveWidget() to obtain TextSelec…

content/browser/renderer_host/text_input_manager.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_MANAGER_H__
 #define CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_MANAGER_H__
 
 #include <unordered_map>
 #include <utility>
 
@@ skipping 88 matching lines @@
 
   // Returns the rect between selection bounds.
   gfx::Rect GetSelectionBoundsRect() const;
 
   // Returns a vector of rects representing the character bounds.
   const std::vector<gfx::Rect>* GetCompositionCharacterBounds() const;
 
   // The following method returns the text selection state for the given |view|.
   // If |view| == nullptr, it will assume |active_view_| and return its state.
   // In the case of |active_view_| == nullptr, the method will return nullptr.
+  // This method will not return nullptr when |view| != nullptr.
   const TextSelection* GetTextSelection(
       RenderWidgetHostViewBase* view = nullptr) const;
 
   // ---------------------------------------------------------------------------
   // The following methods are called by RWHVs on the tab to update their IME-
   // related state.
 
   // Updates the TextInputState for |view|.
   void UpdateTextInputState(RenderWidgetHostViewBase* view,
                             const TextInputState& state);
@@ skipping 91 matching lines @@
   ViewMap<CompositionRangeInfo> composition_range_info_map_;
   ViewMap<TextSelection> text_selection_map_;
 
   base::ObserverList<Observer> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(TextInputManager);
 };
 }
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_MANAGER_H__