Refactor OverlayPanel height calculations

chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java
index b2b8d598c6f48b7252f3de23d789c67fdc813f07..5bface247ab39ef3c82e957911e8addbcd8c3c3d 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/OverlayPanel.java
@@ -281,7 +281,9 @@ public class OverlayPanel extends OverlayPanelAnimation implements ActivityState
         return false;
     }
 
-    @Override
+    /**
+     * @return The absolute amount in DP that the top controls have shifted off screen.
+     */
     protected float getTopControlsOffsetDp() {
         if (mActivity == null || mActivity.getFullscreenManager() == null) return 0.0f;
         return -mActivity.getFullscreenManager().getControlOffset() * mPxToDp;
@@ -798,7 +800,7 @@ public class OverlayPanel extends OverlayPanelAnimation implements ActivityState
     public void onSizeChanged(float width, float height, float visibleViewportOffsetY,
             int orientation) {
         resizePanelContentViewCore(width, height);
-        onSizeChanged(width, height);
+        onSizeChanged(width, height, visibleViewportOffsetY);
     }
 
     /**
@@ -812,11 +814,8 @@ public class OverlayPanel extends OverlayPanelAnimation implements ActivityState
         if (!isShowing()) return;
         ContentViewCore panelContent = getContentViewCore();
         if (panelContent != null) {
-            // Take the height of the toolbar into consideration.
-            int toolbarHeightPx = getTopControlsOffsetDp() > 0
-                    ? 0 : (int) (getToolbarHeight() / mPxToDp);
             panelContent.onSizeChanged((int) (width / mPxToDp),
-                    (int) (height / mPxToDp) + toolbarHeightPx, panelContent.getViewportWidthPix(),
+                    (int) (height / mPxToDp), panelContent.getViewportWidthPix(),
                     panelContent.getViewportHeightPix());
             panelContent.onPhysicalBackingSizeChanged(
                     (int) (width / mPxToDp), (int) (height / mPxToDp));