[Android History] Add tests for removing items

chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java
index c9f0e1dc4627f0099d18e916bba704cdef378d61..e2cd12474bd6c29a6e92644635867f526ef0ec40 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/history/BrowsingHistoryBridge.java
@@ -11,50 +11,22 @@ import java.util.ArrayList;
 import java.util.List;
 
 /** The JNI bridge for Android to fetch and manipulate browsing history. */
-public class BrowsingHistoryBridge {
-
-    /**
-     * Observer to be notified of browsing history events.
-     */
-    public interface BrowsingHistoryObserver {
-        /**
-         * Called after {@link BrowsingHistoryBridge#queryHistory(String, long)} is complete.
-         * @param items The items that matched the #queryHistory() parameters.
-         * @param hasMorePotentialMatches Whether there are more items that match the query text.
-         *                                This will be false once the entire local history database
-         *                                has been searched.
-         */
-        public void onQueryHistoryComplete(List<HistoryItem> items,
-                boolean hasMorePotentialMatches);
-
-        /**
-         * Called when history has been deleted through something other than a call to
-         * BrowsingHistoryBridge#removeItems(). For example, if two instances of the history page
-         * are open and the user removes items in one instance, the other instance will be notified
-         * via this method.
-         */
-        public void onHistoryDeleted();
-
-        /**
-         * Called after querying history to indicate whether other forms of browsing history were
-         * found.
-         * @param hasOtherForms Whether other forms of browsing history were found.
-         * @param hasSyncedResults Whether synced results were found.
-         */
-        public void hasOtherFormsOfBrowsingData(boolean hasOtherForms, boolean hasSyncedResults);
-    }
-
-    private final BrowsingHistoryObserver mObserver;
-
+public class BrowsingHistoryBridge implements HistoryProvider {
+    private BrowsingHistoryObserver mObserver;
     private long mNativeHistoryBridge;
     private boolean mRemovingItems;
     private boolean mHasPendingRemoveRequest;
 
-    public BrowsingHistoryBridge(BrowsingHistoryObserver observer) {
+    public BrowsingHistoryBridge() {
         mNativeHistoryBridge = nativeInit(Profile.getLastUsedProfile());
+    }
+
+    @Override
+    public void setObserver(BrowsingHistoryObserver observer) {
         mObserver = observer;
     }
 
+    @Override
     public void destroy() {
         if (mNativeHistoryBridge != 0) {
             nativeDestroy(mNativeHistoryBridge);
@@ -62,29 +34,17 @@ public class BrowsingHistoryBridge {
         }
     }
 
-    /**
-     * Query browsing history. Only one query may be in-flight at any time. See
-     * BrowsingHistoryService::QueryHistory.
-     * @param query The query search text. May be empty.
-     * @param endQueryTime The end of the time range to search. A value of 0 indicates that there
-     *                     is no limit on the end time. See the native QueryOptions.
-     */
+    @Override
     public void queryHistory(String query, long endQueryTime) {
         nativeQueryHistory(mNativeHistoryBridge, new ArrayList<HistoryItem>(), query, endQueryTime);
     }
 
-    /**
-     * Adds the HistoryItem to the list of items being removed. The removal will not be committed
-     * until {@link #removeItems()} is called.
-     * @param item The item to mark for removal.
-     */
+    @Override
     public void markItemForRemoval(HistoryItem item) {
         nativeMarkItemForRemoval(mNativeHistoryBridge, item.getUrl(), item.getTimestamps());
     }
 
-    /**
-     * Removes all items that have been marked for removal through #markItemForRemoval().
-     */
+    @Override
     public void removeItems() {
         // Only one remove request may be in-flight at any given time. If items are currently being
         // removed, queue the new request and return early.
@@ -105,7 +65,7 @@ public class BrowsingHistoryBridge {
 
     @CalledByNative
     public void onQueryHistoryComplete(List<HistoryItem> items, boolean hasMorePotentialMatches) {
-        mObserver.onQueryHistoryComplete(items, hasMorePotentialMatches);
+        if (mObserver != null) mObserver.onQueryHistoryComplete(items, hasMorePotentialMatches);
     }
 
     @CalledByNative
@@ -123,12 +83,14 @@ public class BrowsingHistoryBridge {
 
     @CalledByNative
     public void onHistoryDeleted() {
-        mObserver.onHistoryDeleted();
+        if (mObserver != null) mObserver.onHistoryDeleted();
     }
 
     @CalledByNative
     public void hasOtherFormsOfBrowsingData(boolean hasOtherForms, boolean hasSyncedResults) {
-        mObserver.hasOtherFormsOfBrowsingData(hasOtherForms, hasSyncedResults);
+        if (mObserver != null) {
+            mObserver.hasOtherFormsOfBrowsingData(hasOtherForms, hasSyncedResults);
+        }
     }
 
     private native long nativeInit(Profile profile);