Export GetLastCommittedEntryIndex and RemoveEntryAtIndex to Java layer

BUG=426679

Review URL: https://codereview.chromium.org/675133002

Cr-Commit-Position: refs/heads/master@{#302408}

chrome/android/javatests/src/org/chromium/chrome/browser/NavigationPopupTest.java

@@ -163,6 +163,16 @@ public class NavigationPopupTest extends ChromeShellTestBase {
         public void goToNavigationIndex(int index) {
             mNavigatedIndex = index;
         }
+
+        @Override
+        public int getLastCommittedEntryIndex() {
+            return -1;
+        }
+
+        @Override
+        public boolean removeEntryAtIndex(int index) {
+            return false;
+        }
     }
 
     @MediumTest

content/browser/frame_host/navigation_controller_android.cc

@@ -311,4 +311,15 @@ NavigationControllerAndroid::GetPendingEntry(JNIEnv* env, jobject obj) {
       env, entry, navigation_controller_->GetPendingEntryIndex());
 }
 
+jint NavigationControllerAndroid::GetLastCommittedEntryIndex(JNIEnv* env,
+                                                             jobject obj) {
+  return navigation_controller_->GetLastCommittedEntryIndex();
+}
+
+jboolean NavigationControllerAndroid::RemoveEntryAtIndex(JNIEnv* env,
+                                                         jobject obj,
+                                                         jint index) {
+  return navigation_controller_->RemoveEntryAtIndex(index);
+}
+
 }  // namespace content

content/browser/frame_host/navigation_controller_android.h

@@ -77,6 +77,8 @@ class CONTENT_EXPORT NavigationControllerAndroid {
   base::android::ScopedJavaLocalRef<jstring>
       GetOriginalUrlForVisibleNavigationEntry(JNIEnv* env, jobject obj);
   void ClearHistory(JNIEnv* env, jobject obj);
+  int GetLastCommittedEntryIndex(JNIEnv* env, jobject obj);
+  jboolean RemoveEntryAtIndex(JNIEnv* env, jobject obj, jint index);
 
  private:
   NavigationController* navigation_controller_;

content/public/android/java/src/org/chromium/content/browser/framehost/NavigationControllerImpl.java

@@ -210,6 +210,22 @@ import org.chromium.content_public.browser.NavigationHistory;
         return null;
     }
 
+    @Override
+    public int getLastCommittedEntryIndex() {
+        if (mNativeNavigationControllerAndroid != 0) {
+            return nativeGetLastCommittedEntryIndex(mNativeNavigationControllerAndroid);
+        }
+        return -1;
+    }
+
+    @Override
+    public boolean removeEntryAtIndex(int index) {
+        if (mNativeNavigationControllerAndroid != 0) {
+            return nativeRemoveEntryAtIndex(mNativeNavigationControllerAndroid, index);
+        }
+        return false;
+    }
+
     @CalledByNative
     private static void addToNavigationHistory(Object history, Object navigationEntry) {
         ((NavigationHistory) history).addEntry((NavigationEntry) navigationEntry);
@@ -264,4 +280,7 @@ import org.chromium.content_public.browser.NavigationHistory;
     private native void nativeSetUseDesktopUserAgent(long nativeNavigationControllerAndroid,
             boolean override, boolean reloadOnChange);
     private native NavigationEntry nativeGetPendingEntry(long nativeNavigationControllerAndroid);
+    private native int nativeGetLastCommittedEntryIndex(long nativeNavigationControllerAndroid);
+    private native boolean nativeRemoveEntryAtIndex(long nativeNavigationControllerAndroid,
+            int index);
 }

content/public/android/java/src/org/chromium/content_public/browser/NavigationController.java

@@ -141,4 +141,16 @@ public interface NavigationController {
      *         exists.
      */
     public NavigationEntry getPendingEntry();
+
+    /**
+     * @return The index of the last committed entry.
+     */
+    public int getLastCommittedEntryIndex();
+
+    /**
+     * Removes the entry at the specified |index|.
+     * @return false, if the index is the last committed index or the pending entry. Otherwise this
+     *         call discards any transient or pending entries.
+     */
+    public boolean removeEntryAtIndex(int index);
 }