Compute pageScaleFactor on page so that fixed layout page fits width of window.

content/renderer/render_widget.h

 // Copyright (c) 2011 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_RENDERER_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 228 matching lines @@
   // given output parameters.
   //
   // A return value of null means optimized painting can not be used and we
   // should continue with the normal painting code path.
   virtual webkit::ppapi::PluginInstance* GetBitmapForOptimizedPluginPaint(
       const gfx::Rect& paint_bounds,
       TransportDIB** dib,
       gfx::Rect* location,
       gfx::Rect* clip);
 
+  // Gets the size of the document according to WebKit.
+  virtual gfx::Size GetContentSize();

[jam, 2011/09/02 17:11:41]

what's the point of adding these virtual methods to RenderWidget if they're only
useful for RenderView, and only RenderView calls these methods?

[Fady Samuel, 2011/09/08 23:46:39]

Done.

+  virtual float GetPageScaleFactor();
+
   // Gets the scroll offset of this widget, if this widget has a notion of
   // scroll offset.
   virtual gfx::Point GetScrollOffset();
 
+

[jam, 2011/09/02 17:11:41]

?

[Fady Samuel, 2011/09/08 23:46:39]

Done.

   // Sets the "hidden" state of this widget.  All accesses to is_hidden_ should
   // use this method so that we can properly inform the RenderThread of our
   // state.
   void SetHidden(bool hidden);
 
   bool is_hidden() const { return is_hidden_; }
 
   // True if an UpdateRect_ACK message is pending.
   bool update_reply_pending() const {
     return update_reply_pending_;
@@ skipping 155 matching lines @@
   // While we are waiting for the browser to update window sizes,
   // we track the pending size temporarily.
   int pending_window_rect_count_;
   WebKit::WebRect pending_window_rect_;
 
   scoped_ptr<IPC::Message> pending_input_event_ack_;
 
   // Indicates if the next sequence of Char events should be suppressed or not.
   bool suppress_next_char_events_;
 
+  // Whether the page scale factor has been set by the page viewport tag or
+  // user. If not, we may choose to zoom out to fit all the content width.
+  bool page_scale_factor_set_;
+
   // Set to true if painting to the window is handled by the accelerated
   // compositor.
   bool is_accelerated_compositing_active_;
 
   base::Time animation_floor_time_;
   bool animation_update_pending_;
   bool animation_task_posted_;
   bool invalidation_task_posted_;
 
   bool has_disable_gpu_vsync_switch_;
   base::TimeTicks last_do_deferred_update_time_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_