Add the ability for keys to be drawn as an image.

services/keyboard_native/key_layout.h

 // Copyright 2015 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 SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_
 #define SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
-#include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/services/geometry/public/interfaces/geometry.mojom.h"
-#include "third_party/skia/include/core/SkCanvas.h"
-#include "ui/gfx/geometry/point.h"
-#include "ui/gfx/geometry/rect.h"
+
+class SkCanvas;
+class SkPaint;
+
+namespace gfx {
+class RectF;
+class Point;
+}
 
 namespace keyboard {
 
 // Represents a drawable keyboard.
 class KeyLayout {
  public:
   // All keys represented by this KeyBoard layout will implement the Key
   // interface.
   class Key {
    public:
     virtual ~Key() {}
 
     // Draws the Key to the SkCanvas with the given SkPaint to the given Rect.
     virtual void Draw(SkCanvas* canvas,
-                      SkPaint paint,
+                      const SkPaint& paint,
                       const gfx::RectF& rect) = 0;
 
     // Converts the Key to its text representation.
     virtual const char* ToText() const = 0;
 
     // Indicate to the Key that a touch up has occurred on it.
     virtual void OnTouchUp() = 0;
   };
 
+  class TextKey;
+
   KeyLayout();
   ~KeyLayout();
 
   // Sets the callback to call with the text of a key whenever it's pressed.
   void SetTextCallback(
       base::Callback<void(const std::string&)> on_text_callback);
 
   // Sets the callback to call whenever delete is pressed.
   void SetDeleteCallback(base::Callback<void()> on_delete_callback);
 
   // Sets the dimensions the keyboard will draw itself into.
   void SetSize(const mojo::Size& size);
 
   // Draws the keyboard to the SkCanvas.
   void Draw(SkCanvas* canvas);
 
   // Returns the Key at the given Point.  Returns nullptr if no key is at that
   // Point.
   Key* GetKeyAtPoint(const gfx::Point& point);
 
   // Indicate to the keyboard that a touch up has occurred at the given Point.
   void OnTouchUp(const gfx::Point& touch_up);
 
  private:
-  // An implementation of Key that draws itself as ASCII text.
-  class TextKey : public Key {
-   public:
-    TextKey(const char* text,
-            base::Callback<void(const TextKey&)> touch_up_callback);
-    ~TextKey() override;
-    void Draw(SkCanvas* canvas, SkPaint paint, const gfx::RectF& rect) override;
-    const char* ToText() const override;
-    void OnTouchUp() override;
-
-   private:
-    const char* text_;
-    base::Callback<void(const TextKey&)> touch_up_callback_;
-
-    DISALLOW_COPY_AND_ASSIGN(TextKey);
-  };
-
   // initializes the *_layout_ vectors.
   void InitLayouts();
 
   // initializes the *_key_map_ vectors.
   void InitKeyMaps();
 
   // A TextKey callback that does nothing.
   void OnKeyDoNothing(const TextKey& key);
 
   // A TextKey callback that calls on_text_callback_ with the text of the
@@ skipping 23 matching lines @@
   std::vector<std::vector<Key*>> upper_case_key_map_;
   std::vector<std::vector<Key*>> symbols_key_map_;
   base::WeakPtrFactory<KeyLayout> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(KeyLayout);
 };
 
 }  // namespace keyboard
 
 #endif  // SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_