Fix screenshots.

Bug: 16861182
Change-Id: I9433cb4a5cc100d85f06eeed18ade3ead5ba8188
diff --git a/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java b/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
index c559253..d4c8ce3 100644
--- a/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
+++ b/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
@@ -429,6 +429,9 @@
         try {
             panelWidth = r.getDimensionPixelSize(R.dimen.notification_panel_width);
         } catch (Resources.NotFoundException e) {
+        }
+        if (panelWidth <= 0) {
+            // includes notification_panel_width==match_parent (-1)
             panelWidth = mDisplayMetrics.widthPixels;
         }
         mPreviewWidth = panelWidth;