CSS: Do not throw on frame elements in FF

IE9-10 throws on elements created in popups (see #14150), FF meanwhile throws
on frame elements through "defaultView.getComputedStyle" (see #15098)

Use "defaultView" if in the popup which would fix IE issue,
use "window.getComputedStyle" which would fix FF issue.

And everybody wins, except performance, but who cares right?

Fixes #15098
Closes gh-1583

1 files changed, 8 insertions, 1 deletions

diff --git a/src/css/var/getStyles.js b/src/css/var/getStyles.js
index 26cc0a25e..413acd04a 100644
--- a/src/css/var/getStyles.js
+++ b/src/css/var/getStyles.js
@@ -1,5 +1,12 @@
 define(function() {
 	return function( elem ) {
-		return elem.ownerDocument.defaultView.getComputedStyle( elem, null );
+		// Support: IE<=11+, Firefox<=30+ (#15098, #14150)
+		// IE throws on elements created in popups
+		// FF meanwhile throws on frame elements through "defaultView.getComputedStyle"
+		if ( elem.ownerDocument.defaultView.opener ) {
+			return elem.ownerDocument.defaultView.getComputedStyle( elem, null );
+		}
+
+		return window.getComputedStyle( elem, null );
 	};
 });