[Offline pages] Minimizing exposure to ChromeActivity in offline pages

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java

Index: chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java
index 929109c91af23ea966816eb47eec433f86d96037..16c95854140136747d91bb5a29c339554ede0351 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageTabObserver.java
@@ -4,8 +4,10 @@
 
 package org.chromium.chrome.browser.offlinepages;
 
+import android.content.Context;
+
 import org.chromium.base.Log;
-import org.chromium.chrome.browser.ChromeActivity;
+import org.chromium.chrome.browser.snackbar.SnackbarManager;
 import org.chromium.chrome.browser.snackbar.SnackbarManager.SnackbarController;
 import org.chromium.chrome.browser.tab.EmptyTabObserver;
 import org.chromium.chrome.browser.tab.Tab;
@@ -21,8 +23,8 @@ import java.util.WeakHashMap;
  */
 public class OfflinePageTabObserver extends EmptyTabObserver {
     private static final String TAG = "OfflinePageTO";
-    private ChromeActivity mActivity;
-    private long mBookmarkId;
+    private Context mContext;
+    private SnackbarManager mSnackbarManager;
     private boolean mConnected;
     private SnackbarController mSnackbarController;
     private boolean mWasHidden;
@@ -33,19 +35,22 @@ public class OfflinePageTabObserver extends EmptyTabObserver {
 
     /**
      * Create and attach a tab observer if we don't already have one, otherwise update it.
-     * @param activity The ChromeActivity we are associated with.
+     * @param context Android context.
+     * @param snackbarManager The snackbar manager to show and dismiss snackbars.
      * @param tab The tab we are adding an observer for.
-     * @param conneted True if we were connected when this call was made.
+     * @param connected True if we were connected when this call was made.
+     * @param snackbarController The snackbar controller to control snackbar behavior.
      */
-    public static void addObserverForTab(ChromeActivity activity, Tab tab, boolean connected,
-            SnackbarController snackbarController) {
+    public static void addObserverForTab(Context context, SnackbarManager snackbarManager, Tab tab,
+            boolean connected, SnackbarController snackbarController) {
         // See if we already have an observer for this tab.
         int tabId = tab.getId();
         OfflinePageTabObserver observer = sTabObservers.get(tabId);
 
         if (observer == null) {
             // If we don't have an observer, build one and attach it to the tab.
-            observer = new OfflinePageTabObserver(activity, tab, connected, snackbarController);
+            observer = new OfflinePageTabObserver(
+                    context, snackbarManager, tab, connected, snackbarController);
             sTabObservers.put(tabId, observer);
             tab.addObserver(observer);
         } else {
@@ -63,62 +68,36 @@ public class OfflinePageTabObserver extends EmptyTabObserver {
     }
 
     /**
-     * Removes tab observer for a given bookmark.
-     * @param bookmarkId The bookmarkId we are removing an observer for.
-     */
-    public static void removeObserverForBookmark(long bookmarkId) {
-        // Find any observer, if we have one.
-        int tabId = findTabIdByObserverBookmarkId(bookmarkId);
-        Log.d(TAG, "removeObserver called, tabId " + tabId + ", bookmarkId " + bookmarkId);
-        if (tabId == Tab.INVALID_TAB_ID) return;
-
-        removeObserverForTab(tabId);
-    }
-
-    /**
      * Removes the observer for a tab with the specified tabId.
-     * @param tabId The Id of the tab to remove an observer for.
+     * @param tab The tab to remove an observer for.
      */
-    private static void removeObserverForTab(int tabId) {
-        OfflinePageTabObserver observer = sTabObservers.get(tabId);
-        sTabObservers.remove(tabId);
+    private static void removeObserverForTab(Tab tab) {
+        OfflinePageTabObserver observer = sTabObservers.get(tab.getId());
         if (observer != null) {
-            Tab tab = observer.mActivity.getTabModelSelector().getTabById(tabId);
             tab.removeObserver(observer);
         }
-    }
-    /**
-     * Finds the tab ID of the observer with the specified bookmark ID, if it exists.  Returns an
-     * invalid tab ID if none found.
-     * @param bookmarkId The bookmark ID on the observer on the searched for tab.
-     * @return ID of the tab associated with this bookmark, or Tab.INVALID_TAB_ID if none found.
-     */
-    private static int findTabIdByObserverBookmarkId(long bookmarkId) {
-        // Iterate over the whole map looking for a bookmark ID that matches.
-        for (Map.Entry<Integer, OfflinePageTabObserver> entry : sTabObservers.entrySet()) {
-            OfflinePageTabObserver value = (OfflinePageTabObserver) entry.getValue();
-            if (value != null && value.mBookmarkId == bookmarkId) return entry.getKey();
-        }
-        return Tab.INVALID_TAB_ID;
+        sTabObservers.remove(tab.getId());
     }
 
     /**
      * Builds a new OfflinePageTabObserver.
-     * @param activity The ChromeActivity of this instance of the browser.
+     * @param context Android context.
+     * @param snackbarManager The snackbar manager to show and dismiss snackbars.
+     * @param tab The tab we are adding an observer for.
      * @param connected True if the phone is connected when the observer is created.
-     * @param bookmarkId Id of the bookmark (offline page) that is associated with this observer.
      * @param snackbarController Controller to use to build the snackbar.
      */
-    public OfflinePageTabObserver(ChromeActivity activity, Tab tab, boolean connected,
-            SnackbarController snackbarController) {
-        mActivity = activity;
-        mBookmarkId = tab.getBookmarkId();
+    OfflinePageTabObserver(Context context, SnackbarManager snackbarManager, Tab tab,
+            boolean connected, SnackbarController snackbarController) {
+        mContext = context;
+        mSnackbarManager = snackbarManager;
         mConnected = connected;
         // Remember if the tab was hidden when we started, so we can show the snackbar when
         // the tab becomes visible.
         mWasHidden = tab.isHidden();
 
-        mListener = new OfflinePageConnectivityListener(activity, tab, snackbarController);
+        mListener = new OfflinePageConnectivityListener(
+                context, snackbarManager, tab, snackbarController);
         mSnackbarController = snackbarController;
     }
 
@@ -139,7 +118,8 @@ public class OfflinePageTabObserver extends EmptyTabObserver {
 
         if (mWasHidden) {
             if (mConnected) {
-                OfflinePageUtils.showReloadSnackbar(mActivity, mSnackbarController);
+                OfflinePageUtils.showReloadSnackbar(
+                        mContext, mSnackbarManager, mSnackbarController);
             }
 
             mWasHidden = false;
@@ -151,12 +131,12 @@ public class OfflinePageTabObserver extends EmptyTabObserver {
     public void onHidden(Tab hiddenTab) {
         mWasHidden = true;
         // In case any snackbars are showing, dismiss them before we switch tabs.
-        mActivity.getSnackbarManager().dismissSnackbars(mSnackbarController);
+        mSnackbarManager.dismissSnackbars(mSnackbarController);
     }
 
     @Override
     public void onPageLoadStarted(Tab tab, String newUrl) {
-        OfflinePageUtils.preferOnlineVersion(mActivity, tab, newUrl);
+        OfflinePageUtils.preferOnlineVersion(tab, newUrl);
     }
 
     @Override
@@ -173,9 +153,9 @@ public class OfflinePageTabObserver extends EmptyTabObserver {
         // Unregister this tab for OS connectivity notifications.
         mListener.disable();
         Log.d(TAG, "onUrlUpdated");
-        removeObserverForTab(reloadingTab.getId());
+        removeObserverForTab(reloadingTab);
         // In case any snackbars are showing, dismiss them before we navigate away.
-        mActivity.getSnackbarManager().dismissSnackbars(mSnackbarController);
+        mSnackbarManager.dismissSnackbars(mSnackbarController);
     }
 
     /**