[CRD iOS] Some fixes for rendering

remoting/client/display/canvas.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 REMOTING_CLIENT_DISPLAY_CANVAS_H_
 #define REMOTING_CLIENT_DISPLAY_CANVAS_H_
 
 #include <array>
 
 #include "base/macros.h"
@@ skipping 19 matching lines @@
   //
   // | m0, m1, m2, |   | x |
   // | m3, m4, m5, | * | y |
   // | m6, m7, m8  |   | 1 |
   //
   // For a typical transformation matrix such that m1=m3=m6=m7=0 and m8=1, m0
   // and m4 defines the scaling factor of the canvas and m2 and m5 defines the
   // offset of the upper-left corner in pixel.
   virtual void SetTransformationMatrix(const std::array<float, 9>& matrix) = 0;
 
-  // Sets the size of the view in pixels.
+  // Sets the size of the view in pixels such that it fills up the the whole
+  // viewport.
+  // Note that this only affects the transformation matrix. It doesn't affect
+  // how the viewport is rendered on the screen.
   virtual void SetViewSize(int width, int height) = 0;
 
   // Draws the texture on the canvas. Nothing will happen if
   // SetNormalizedTransformation() has not been called.
   // vertex_buffer: reference to the 2x4x2 float vertex buffer.
   //                [ four (x, y) position of the texture vertices in pixel
   //                              with respect to the canvas,
   //                  four (x, y) position of the vertices in percentage
   //                              defining the visible area of the texture ]
   // alpha_multiplier: Will be multiplied with the alpha channel of the texture.
@@ skipping 14 matching lines @@
   // Intended to be given to a Drawable to draw onto.
   virtual base::WeakPtr<Canvas> GetWeakPtr() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Canvas);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_CLIENT_DISPLAY_CANVAS_H_