Refactor OverlayPanel height calculations

chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java
index f44df724948eae71652d450bdefba401a9b2a668..94f05c7f675260bf859a7f2885adc9ddcef75882 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/Layout.java
@@ -374,10 +374,9 @@ public abstract class Layout implements TabContentManager.ThumbnailChangeListene
      */
     public final void sizeChanged(RectF availableViewport, RectF visibleViewport,
             RectF screenViewport, float heightMinusTopControls, int orientation) {
-        // 1. Pull out this Layout's specific width and height properties based on the available
-        // viewport.
-        float width = availableViewport.width();
-        float height = availableViewport.height();
+        // 1. Pull out this Layout's width and height properties based on the viewport.
+        float width = screenViewport.width();
+        float height = screenViewport.height();
 
         // 2. Check if any Layout-specific properties have changed.
         boolean layoutPropertiesChanged = mWidth != width