Clean up WebAppActivity tab save/reload

This is cleanup in preparation for
https://chromium-review.googlesource.com/c/chromium/src/+/1313556, but
is probably worth it on its own as it puts all of the logic for save/
restore into WebAppActivity instead of having dependent logic split
across SingleTab and WebApp Activity.

Change-Id: Ibdf372e6c3a6be3f7d546a071162ed7a11a5f613
Reviewed-on: https://chromium-review.googlesource.com/c/1329544
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608402}

chrome/android/java/src/org/chromium/chrome/browser/FullscreenActivity.java

@@ -6,6 +6,7 @@ package org.chromium.chrome.browser;
 
 import android.content.ComponentName;
 import android.content.Intent;
+import android.os.Bundle;
 import android.provider.Browser;
 import android.util.SparseArray;
 import android.view.View;
@@ -219,4 +220,9 @@ public class FullscreenActivity extends SingleTabActivity {
         sTabsToSteal.remove(id);
         return tab;
     }
+
+    @Override
+    protected Tab restoreTab(Bundle savedInstanceState) {
+        return null;
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/SingleTabActivity.java

@@ -5,11 +5,11 @@
 package org.chromium.chrome.browser;
 
 import android.content.Intent;
+import android.os.Bundle;
 import android.util.Pair;
 
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabDelegateFactory;
-import org.chromium.chrome.browser.tab.TabUma.TabCreationState;
 import org.chromium.chrome.browser.tabmodel.SingleTabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
@@ -18,8 +18,6 @@ import org.chromium.chrome.browser.tabmodel.document.TabDelegate;
 import org.chromium.content_public.browser.ChildProcessImportance;
 import org.chromium.content_public.browser.LoadUrlParams;
 
-import java.io.File;
-
 /**
  * Base class for task-focused activities that need to display a single tab.
  *
@@ -27,9 +25,6 @@ import java.io.File;
  * activities - anything where maintaining multiple tabs is unnecessary.
  */
 public abstract class SingleTabActivity extends ChromeActivity {
-    protected static final String BUNDLE_TAB_ID = "tabId";
-    protected static final String BUNDLE_TAB_URL = "tabUrl";
-
     @Override
     protected void onNewIntent(Intent intent) {
         super.onNewIntent(intent);
@@ -83,19 +78,9 @@ public abstract class SingleTabActivity extends ChromeActivity {
         Tab tab = null;
         boolean unfreeze = false;
 
-        int tabId = Tab.INVALID_TAB_ID;
-        String tabUrl = null;
         if (getSavedInstanceState() != null) {
-            tabId = getSavedInstanceState().getInt(BUNDLE_TAB_ID, Tab.INVALID_TAB_ID);
-            tabUrl = getSavedInstanceState().getString(BUNDLE_TAB_URL);
-        }
-
-        if (tabId != Tab.INVALID_TAB_ID && tabUrl != null && getActivityDirectory() != null) {
-            // Restore the tab.
-            TabState tabState = TabState.restoreTabState(getActivityDirectory(), tabId);
-            tab = new Tab(tabId, Tab.INVALID_TAB_ID, false, getWindowAndroid(),
-                    TabLaunchType.FROM_RESTORE, TabCreationState.FROZEN_ON_RESTORE, tabState);
-            unfreeze = true;
+            tab = restoreTab(getSavedInstanceState());
+            if (tab != null) unfreeze = true;
         }
 
         if (tab == null) {
@@ -114,12 +99,7 @@ public abstract class SingleTabActivity extends ChromeActivity {
         return new TabDelegateFactory();
     }
 
-    /**
-     * @return {@link File} pointing at a directory specific for this class.
-     */
-    protected File getActivityDirectory() {
-        return null;
-    }
+    protected abstract Tab restoreTab(Bundle savedInstanceState);
 
     @Override
     protected boolean handleBackPressed() {

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java

@@ -48,6 +48,8 @@ import org.chromium.chrome.browser.tab.EmptyTabObserver;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabDelegateFactory;
 import org.chromium.chrome.browser.tab.TabObserver;
+import org.chromium.chrome.browser.tab.TabUma.TabCreationState;
+import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.document.TabDelegate;
 import org.chromium.chrome.browser.toolbar.top.ToolbarControlContainer;
 import org.chromium.chrome.browser.util.ColorUtils;
@@ -84,6 +86,8 @@ public class WebappActivity extends SingleTabActivity {
     private static final String HISTOGRAM_NAVIGATION_STATUS = "Webapp.NavigationStatus";
     private static final long MS_BEFORE_NAVIGATING_BACK_FROM_INTERSTITIAL = 1000;
 
+    private static final String BUNDLE_TAB_ID = "tabId";
+
     private static final int ENTER_IMMERSIVE_MODE_DELAY_MILLIS = 300;
     private static final int RESTORE_IMMERSIVE_MODE_DELAY_MILLIS = 3000;
     static final int IMMERSIVE_MODE_UI_FLAGS = View.SYSTEM_UI_FLAG_LAYOUT_STABLE
@@ -303,10 +307,8 @@ public class WebappActivity extends SingleTabActivity {
     @Override
     protected void onSaveInstanceState(Bundle outState) {
         super.onSaveInstanceState(outState);
-        if (getActivityTab() != null) {
-            outState.putInt(BUNDLE_TAB_ID, getActivityTab().getId());
-            outState.putString(BUNDLE_TAB_URL, getActivityTab().getUrl());
-        }
+        mDirectoryManager.cancelCleanup();
+        saveState(outState);
     }
 
     @Override
@@ -318,8 +320,6 @@ public class WebappActivity extends SingleTabActivity {
     @Override
     public void onStopWithNative() {
         super.onStopWithNative();
-        mDirectoryManager.cancelCleanup();
-        if (getActivityTab() != null) saveState(getActivityDirectory());
         if (getFullscreenManager() != null) {
             getFullscreenManager().exitPersistentFullscreenMode();
         }
@@ -328,9 +328,16 @@ public class WebappActivity extends SingleTabActivity {
     /**
      * Saves the tab data out to a file.
      */
-    void saveState(File activityDirectory) {
+    private void saveState(Bundle outState) {
+        if (getActivityTab() == null || getActivityTab().getUrl() == null
+                || getActivityTab().getUrl().isEmpty()) {
+            return;
+        }
+
+        outState.putInt(BUNDLE_TAB_ID, getActivityTab().getId());
+
         String tabFileName = TabState.getTabStateFilename(getActivityTab().getId(), false);
-        File tabFile = new File(activityDirectory, tabFileName);
+        File tabFile = new File(getActivityDirectory(), tabFileName);
 
         // Temporarily allowing disk access while fixing. TODO: http://crbug.com/525781
         StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskWrites();
@@ -344,6 +351,19 @@ public class WebappActivity extends SingleTabActivity {
         }
     }
 
+    @Override
+    protected Tab restoreTab(Bundle savedInstanceState) {
+        int tabId = getSavedInstanceState().getInt(BUNDLE_TAB_ID, Tab.INVALID_TAB_ID);
+
+        if (tabId == Tab.INVALID_TAB_ID || getActivityDirectory() == null) return null;
+
+        TabState tabState = TabState.restoreTabState(getActivityDirectory(), tabId);
+        if (tabState == null) return null;
+
+        return new Tab(tabId, Tab.INVALID_TAB_ID, false, getWindowAndroid(),
+                TabLaunchType.FROM_RESTORE, TabCreationState.FROZEN_ON_RESTORE, tabState);
+    }
+
     @Override
     public void onWindowFocusChanged(boolean hasFocus) {
         super.onWindowFocusChanged(hasFocus);
@@ -822,8 +842,7 @@ public class WebappActivity extends SingleTabActivity {
      *
      * @return The directory used for the current web app.
      */
-    @Override
-    protected final File getActivityDirectory() {
+    private File getActivityDirectory() {
         return mDirectoryManager.getWebappDirectory(this, getActivityId());
     }
 

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java

@@ -61,7 +61,6 @@ public class WebappDirectoryManager {
      *
      * @param context         Context to pull info and Files from.
      * @param currentWebappId ID for the currently running web app.
-     * @return                AsyncTask doing the cleaning.
      */
     public void cleanUpDirectories(final Context context, final String currentWebappId) {
         if (mCleanupTask != null) return;