Experimental viewport meta tag support for desktop

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 44dd2840eeedf588b0cd1ba339ea46669a319107..811c2037d916c7e964e5244271c18cf7ae92c2aa 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -663,7 +663,15 @@ WebPreferences WebContentsImpl::GetWebkitPrefs(RenderViewHost* rvh,
 
   prefs.number_of_cpu_cores = base::SysInfo::NumberOfProcessors();
 
-  prefs.viewport_enabled = command_line.HasSwitch(switches::kEnableViewport);
+  prefs.viewport_meta_enabled =
+      command_line.HasSwitch(switches::kEnableViewportMeta);
+
+  prefs.viewport_enabled =
+      command_line.HasSwitch(switches::kEnableViewport) ||
+      prefs.viewport_meta_enabled;

[aelias_OOO_until_Jul13, 2013/10/25 04:13:27]

This effectively turns on @viewport support for Android which we are not ready
to ship yet.  Please remove the || and keep the flags entirely separate.

[kenneth.r.christiansen, 2013/10/25 06:27:01]

There is a separate runtime flag for that only enabled with
--enable-experimental-web-platform-features

[bokan, 2013/10/25 17:19:33]

--viewport-enabled is already on in Android and I didn't change how it behaves
except that it needs --viewport-meta-enabled to process any legacy viewport
tags. As Kenneth mentions, you need an additional flag to enable @viewport. The
idea here is that eventually we'd be able to turn on @viewport (using
--enable-viewport) without turning on viewport meta. Android would then add
--enable-viewport-meta to support both. 

[bokan, 2013/10/25 17:19:33]

I was actually unaware that --enable-viewport doesn't turn on @viewport. Does
the experimental flag only apply to author stylesheets? The UA stylesheet has an
@viewport rule in it that seems to be respected (in WebFrame tests at least)
without the additional flag. Is this correct?

[aelias_OOO_until_Jul13, 2013/10/31 20:54:26]

Yes, as discussed on the Blink-side patch, it's always respected for UA
stylesheets.

+
+  prefs.scale_viewport_on_resize =
+      command_line.HasSwitch(switches::kScaleViewportOnResize);
 
   prefs.deferred_image_decoding_enabled =
       command_line.HasSwitch(switches::kEnableDeferredImageDecoding) ||