[Android WebView] Treat zero values in viewport arguments specially

Source/core/dom/ViewportArguments.h

Index: Source/core/dom/ViewportArguments.h
diff --git a/Source/core/dom/ViewportArguments.h b/Source/core/dom/ViewportArguments.h
index ea9a44e60a3897fc7dea694aa2383cfdc953ff9b..d8dada5e37aa9786fe3d5a2b2d6d468ad3de5aa0 100644
--- a/Source/core/dom/ViewportArguments.h
+++ b/Source/core/dom/ViewportArguments.h
@@ -54,7 +54,7 @@ struct ViewportArguments {
         HandheldFriendlyMeta,
         MobileOptimizedMeta,
         ViewportMeta,
-        ViewportMetaLayoutSizeQuirk,
+        ViewportMetaLayoutSizeAndZeroValuesQuirk,

[rune, 2013/09/02 06:25:14]

Is it important that these quirks can be turned on/off and change effect during
the lifetime of a WebView?

If not, I think I would have done the quirks during viewport meta tag
processing, and not as part of ViewportArguments::resolve. That will make
ViewportArguments::resolve less cluttery and make it possible to remove these
modes completely.

I see now that it's not possible to skip the extend-width part like that with
the current code, but still I'd like to know if changing that setting needs to
have an effect on a document that is already loaded in that WebView. Just to
know how we can rewrite this quirk for the new code.

[kenneth.r.christiansen, 2013/09/02 06:45:04]

I would also really like to have these be runtime settings instead of tied into
the ViewportArguments as a specialized type

[mnaganov (inactive), 2013/09/02 13:25:53]

No. We can assume that they are constant during the lifetime of a WebView.
Not everything can be easily done during the processing stage, as sometimes
decisions depend on the values of other fields of the tag. While during the
processing stage the fields are considered independently. But thanks to your
proposal, I have found that at least it is possible to separate those two
quirks.
 

         CSSDeviceAdaptation
     } type;