Introduce ManifestUpgradeDetector for WebAPK to detect web manifest changes.

chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java

Index: chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
index b168c932c13076965547540bdaf3e825c40061ae..aad35a7a11274cc358749e0ecffc5c6ca87c23b1 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
@@ -84,6 +84,7 @@ import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
 import org.chromium.chrome.browser.tabmodel.TabModelImpl;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabReparentingParams;
+import org.chromium.chrome.browser.webapps.ManifestUpgradeDetector;
 import org.chromium.components.dom_distiller.core.DomDistillerUrlUtils;
 import org.chromium.components.navigation_interception.InterceptNavigationDelegate;
 import org.chromium.components.security_state.ConnectionSecurityLevel;
@@ -183,6 +184,8 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
     /** Manages app banners shown for this tab. */
     private AppBannerManager mAppBannerManager;
 
+    private ManifestUpgradeDetector mManifestUpgradeDetector;
+
     /** Controls overscroll pull-to-refresh behavior for this tab. */
     private SwipeRefreshHandler mSwipeRefreshHandler;
 
@@ -1440,6 +1443,11 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
                 if (mAppBannerManager != null) addObserver(mAppBannerManager);
             }
 
+            if (ManifestUpgradeDetector.isEnabled()) {
+                mManifestUpgradeDetector = mDelegateFactory.createManifestUpgradeDetector(this);
+                if (mManifestUpgradeDetector != null) addObserver(mManifestUpgradeDetector);
+            }
+
             mTopControlsVisibilityDelegate =
                     mDelegateFactory.createTopControlsVisibilityDelegate(this);
 
@@ -1562,6 +1570,7 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
         mTopControlsVisibilityDelegate = mDelegateFactory.createTopControlsVisibilityDelegate(this);
         setInterceptNavigationDelegate(mDelegateFactory.createInterceptNavigationDelegate(this));
         mAppBannerManager = mDelegateFactory.createAppBannerManager(this);
+        mManifestUpgradeDetector = mDelegateFactory.createManifestUpgradeDetector(this);
 
         // Reload the NativePage (if any), since the old NativePage has a reference to the old
         // activity.
@@ -2038,6 +2047,10 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
             mAppBannerManager = null;
         }
 
+        if (mManifestUpgradeDetector != null) {
+            mManifestUpgradeDetector.destroy();
+            mManifestUpgradeDetector = null;
+        }
         mPreviousFullscreenTopControlsOffsetY = Float.NaN;
         mPreviousFullscreenContentOffsetY = Float.NaN;
 
@@ -3008,6 +3021,18 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
         return mAppBannerManager;
     }
 
+    /**
+     * @return the ManifestUpgradeDetector.
+     */
+    @VisibleForTesting
+    public ManifestUpgradeDetector getManifestUpgradeDetectorForTesting() {
+        return mManifestUpgradeDetector;
+    }
+
+    @VisibleForTesting
+    public void setManifestUpgradeDetectorForTesting(ManifestUpgradeDetector detector) {
+        mManifestUpgradeDetector = detector;
+    }
     @VisibleForTesting
     public boolean hasPrerenderedUrl(String url) {
         return nativeHasPrerenderedUrl(mNativeTabAndroid, url);