[Home] Don't cache FadingBackgroundView

chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java
index 4515d9746faf7addecc195bb992be1ad7de7410d..3cbd1643a04caf4d09eae5ba5c5eb2b3a2c1c27d 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/ChromeHomeNewTabPageBase.java
@@ -36,7 +36,6 @@ public abstract class ChromeHomeNewTabPageBase implements NativePage {
     @Nullable
     final LayoutManagerChrome mLayoutManager;
     final BottomSheet mBottomSheet;
-    final View mFadingBackgroundView;
     final String mTitle;
 
     private boolean mShowOverviewOnClose;
@@ -57,7 +56,6 @@ public abstract class ChromeHomeNewTabPageBase implements NativePage {
         mTab = tab;
         mTabModelSelector = tabModelSelector;
         mLayoutManager = layoutManager;
-        mFadingBackgroundView = mTab.getActivity().getFadingBackgroundView();
         mBottomSheet = mTab.getActivity().getBottomSheet();
         mTitle = context.getResources().getString(R.string.button_new_tab);
 
@@ -87,7 +85,7 @@ public abstract class ChromeHomeNewTabPageBase implements NativePage {
 
             @Override
             public void onHidden(Tab tab) {
-                mFadingBackgroundView.setEnabled(true);
+                mTab.getActivity().getFadingBackgroundView().setEnabled(true);
                 if (!mTab.isClosing()) mShowOverviewOnClose = false;
             }
         };
@@ -130,7 +128,7 @@ public abstract class ChromeHomeNewTabPageBase implements NativePage {
     public void destroy() {
         // The next tab will be selected before this one is destroyed. If the currently selected
         // tab is a Chrome Home new tab page, the FadingBackgroundView should not be enabled.
-        mFadingBackgroundView.setEnabled(
+        mTab.getActivity().getFadingBackgroundView().setEnabled(
                 !isTabChromeHomeNewTabPage(mTabModelSelector.getCurrentTab()));
 
         if (mLayoutManager != null) {
@@ -140,7 +138,9 @@ public abstract class ChromeHomeNewTabPageBase implements NativePage {
     }
 
     private void onNewTabPageShown() {
-        mFadingBackgroundView.setEnabled(false);
+        if (mTab.getActivity().getFadingBackgroundView() != null) {
+            mTab.getActivity().getFadingBackgroundView().setEnabled(false);
+        }
 
         // This method may be called when an NTP is selected due to the user switching tab models.
         // In this case, we do not want the bottom sheet to open. Unfortunately, without observing