Fix tests to avoid page scale reset when setting page scale.

Source/WebKit/chromium/src/WebViewImpl.cpp

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@@ skipping 2853 matching lines @@
 
 void WebViewImpl::setPageScaleFactor(float scaleFactor, const WebPoint& origin)
 {
     if (!page())
         return;
 
     IntPoint newScrollOffset = origin;
     scaleFactor = clampPageScaleFactorToLimits(scaleFactor);
     newScrollOffset = clampOffsetAtScale(newScrollOffset, scaleFactor);
 
+    // Since we are about to explicitly set the page scale factor, this should
+    // cancel out any outstanding reset request.
+    m_pageScaleConstraintsSet.setNeedsReset(false);

[aelias_OOO_until_Jul13, 2013/07/02 22:59:33]

This is a somewhat subtle initialization-timing change to production code and I
think we should avoid this kind of thing to fix tests.  How about instead making
the test code call setInitialPageScaleOverride(-1) when it tries to set the
scale?

[wjmaclean, 2013/07/03 14:12:23]

OK, but are we sure there's no way this "subtle timing" issue can ever bite us
in production web sites? If so, then I'm fine with this approach.

[aelias_OOO_until_Jul13, 2013/07/08 00:53:20]

I don't currently know of a bug here, but it's possible one may be discovered in
the future.  If that happens, it should be tested by a C++ unit test anyway.  I
think the layout tests should all pass regardless of the timing details.

     page()->setPageScaleFactor(scaleFactor, newScrollOffset);
 }
 
 void WebViewImpl::setPageScaleFactorPreservingScrollOffset(float scaleFactor)
 {
     if (clampPageScaleFactorToLimits(scaleFactor) == pageScaleFactor())
         return;
 
     IntPoint scrollOffset(mainFrame()->scrollOffset().width, mainFrame()->scrollOffset().height);
     setPageScaleFactor(scaleFactor, scrollOffset);
@@ skipping 1240 matching lines @@
 }
 
 bool WebViewImpl::shouldDisableDesktopWorkarounds()
 {
     ViewportArguments arguments = mainFrameImpl()->frame()->document()->viewportArguments();
     return arguments.width == ViewportArguments::ValueDeviceWidth || !arguments.userZoom
         || (arguments.minZoom == arguments.maxZoom && arguments.minZoom != ViewportArguments::ValueAuto);
 }
 
 } // namespace WebKit