Refactor viewport initialization logic out of WebViewImpl.

Source/core/testing/Internals.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 Apple 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 888 matching lines @@
     else {
         ec = SYNTAX_ERR;
         return;
     }
 
     pagination.gap = gap;
     pagination.pageLength = pageLength;
     page->setPagination(pagination);
 }
 
+static FloatSize convertToUserSpace(const FloatSize& deviceSize, float devicePixelRatio)

[abarth-chromium, 2013/05/20 18:22:25]

What is "user space" ?

+{
+    FloatSize result = deviceSize;
+    if (devicePixelRatio != 1)
+        result.scale(1 / devicePixelRatio);
+    return result;
+}
+
+static ViewportAttributes computeViewportAttributes(ViewportArguments args, int desktopWidth, int deviceWidth, int deviceHeight, float devicePixelRatio, IntSize visibleViewport)
+{
+    FloatSize initialViewportSize = convertToUserSpace(visibleViewport, devicePixelRatio);
+    FloatSize deviceSize = convertToUserSpace(FloatSize(deviceWidth, deviceHeight), devicePixelRatio);
+
+    return args.resolve(initialViewportSize, deviceSize, desktopWidth);
+}
+
+static float computeMinimumScaleFactorForContentContained(const ViewportAttributes& result, const IntSize& visibleViewport, const IntSize& contentsSize)
+{
+    FloatSize viewportSize(visibleViewport);
+    return max<float>(result.minimumScale, max(viewportSize.width() / contentsSize.width(), viewportSize.height() / contentsSize.height()));
+}
+
+static void restrictMinimumScaleFactorToViewportSize(ViewportAttributes& result, IntSize visibleViewport, float devicePixelRatio)
+{
+    FloatSize viewportSize = convertToUserSpace(visibleViewport, devicePixelRatio);
+
+    result.minimumScale = max<float>(result.minimumScale, max(viewportSize.width() / result.layoutSize.width(), viewportSize.height() / result.layoutSize.height()));
+}

[abarth-chromium, 2013/05/20 18:22:25]

I don't understand why we need all of this code in Internals.  Maybe we should
output information in a different format that requires less computation?

+
 String Internals::configurationForViewport(Document* document, float devicePixelRatio, int deviceWidth, int deviceHeight, int availableWidth, int availableHeight, ExceptionCode& ec)
 {
     if (!document || !document->page()) {
         ec = INVALID_ACCESS_ERR;
         return String();
     }
     Page* page = document->page();
 
     const int defaultLayoutWidthForNonMobilePages = 980;
 
     ViewportArguments arguments = page->viewportArguments();
     ViewportAttributes attributes = computeViewportAttributes(arguments, defaultLayoutWidthForNonMobilePages, deviceWidth, deviceHeight, devicePixelRatio, IntSize(availableWidth, availableHeight));
     restrictMinimumScaleFactorToViewportSize(attributes, IntSize(availableWidth, availableHeight), devicePixelRatio);
-    restrictScaleFactorToInitialScaleIfNotUserScalable(attributes);
 
-    return "viewport size " + String::number(attributes.layoutSize.width()) + "x" + String::number(attributes.layoutSize.height()) + " scale " + String::number(attributes.initialScale) + " with limits [" + String::number(attributes.minimumScale) + ", " + String::number(attributes.maximumScale) + "] and userScalable " + (attributes.userScalable ? "true" : "false");
+    return "viewport size " + String::number(attributes.layoutSize.width()) + "x" + String::number(attributes.layoutSize.height()) + " scale " + String::number(attributes.initialScale) + " with limits [" + String::number(attributes.minimumScale) + ", " + String::number(attributes.maximumScale) + "] and userScalable " + (arguments.userZoom ? "true" : "false");
 }
 
 bool Internals::wasLastChangeUserEdit(Element* textField, ExceptionCode& ec)
 {
     if (!textField) {
         ec = INVALID_ACCESS_ERR;
         return false;
     }
 
     if (HTMLInputElement* inputElement = textField->toInputElement())
@@ skipping 1003 matching lines @@
 
     RenderObject* renderer = select->renderer();
     if (!renderer->isMenuList())
         return false;
 
     RenderMenuList* menuList = toRenderMenuList(renderer);
     return menuList->popupIsVisible();
 }
 
 }