Compute pageScaleFactor on page so that fixed layout page fits width of window.

content/public/common/content_switches.cc

Index: content/public/common/content_switches.cc
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 9f4a5312e95a50a025ec0cf57556d588bc6bb3da..13d69938b4eecbd2bb44dd1c830f973b5565611a 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -200,6 +200,10 @@ const char kEnableDNSCertProvenanceChecking[] =
 // Enables device motion events.
 const char kEnableDeviceMotion[]            = "enable-device-motion";
 
+// By default, a page is laid out to fill the entire width of the window.
+// This flag fixes the layout of the page to a default of 980px.
+const char kEnableFixedLayout[]             = "enable-fixed-layout";
+
 // Enable the JavaScript Full Screen API.
 const char kDisableFullScreen[]             = "disable-fullscreen";