Don't let rounding prematurely influence document size when printing

third_party/WebKit/public/web/WebFrame.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 67 matching lines @@
 class WebString;
 class WebURL;
 class WebURLLoader;
 class WebURLRequest;
 class WebView;
 enum class WebSandboxFlags;
 struct WebConsoleMessage;
 struct WebFindOptions;
 struct WebFloatPoint;
 struct WebFloatRect;
+struct WebFloatSize;
 struct WebFrameOwnerProperties;
 struct WebPoint;
 struct WebPrintParams;
 struct WebRect;
 struct WebScriptSource;
 struct WebSize;
 struct WebURLLoaderOptions;
 
 template <typename T> class WebVector;
 
@@ skipping 402 matching lines @@
     virtual bool isPageBoxVisible(int pageIndex) = 0;
 
     // Returns true if the page style has custom size information.
     virtual bool hasCustomPageSizeStyle(int pageIndex) = 0;
 
     // Returns the preferred page size and margins in pixels, assuming 96
     // pixels per inch. pageSize, marginTop, marginRight, marginBottom,
     // marginLeft must be initialized to the default values that are used if
     // auto is specified.
     virtual void pageSizeAndMarginsInPixels(int pageIndex,
-                                            WebSize& pageSize,
-                                            int& marginTop,
-                                            int& marginRight,
-                                            int& marginBottom,
-                                            int& marginLeft) = 0;
+        WebFloatSize& pageSize,

[Lei Zhang, 2016/07/06 18:26:45]

nit: Is this the correct style for Blink?

+        int& marginTop,
+        int& marginRight,
+        int& marginBottom,
+        int& marginLeft) = 0;
 
     // Returns the value for a page property that is only defined when printing.
     // printBegin must have been called before this method.
     virtual WebString pageProperty(const WebString& propertyName, int pageIndex) = 0;
 
 
     // Events --------------------------------------------------------------
 
     // Dispatches a message event on the current DOMWindow in this WebFrame.
     virtual void dispatchMessageEventWithOriginCheck(
@@ skipping 77 matching lines @@
     WebFrame* m_firstChild;
     WebFrame* m_lastChild;
 
     WebFrame* m_opener;
     WebPrivateOwnPtr<OpenedFrameTracker> m_openedFrameTracker;
 };
 
 } // namespace blink
 
 #endif