[android_webview] Factor AwWebContentsObserver out of AwContentsClient.

android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.android_webview;
+
+import org.chromium.content.browser.WebContentsObserverAndroid;
+import org.chromium.content_public.browser.WebContents;
+import org.chromium.net.NetError;
+
+/**
+ * Routes notifications from WebContents to AwContentsClient and other listeners.
+ */
+public class AwWebContentsObserver extends WebContentsObserverAndroid {
+    private final AwContentsClient mAwContentsClient;
+
+    public AwWebContentsObserver(WebContents webContents, AwContentsClient awContentsClient) {
+        super(webContents);
+        mAwContentsClient = awContentsClient;
+    }
+
+    @Override
+    public void didFinishLoad(long frameId, String validatedUrl, boolean isMainFrame) {
+        String unreachableWebDataUrl = AwContentsStatics.getUnreachableWebDataUrl();
+        boolean isErrorUrl =
+                unreachableWebDataUrl != null && unreachableWebDataUrl.equals(validatedUrl);
+        if (isMainFrame && !isErrorUrl) {
+            mAwContentsClient.onPageFinished(validatedUrl);
+        }
+    }
+
+    @Override
+    public void didFailLoad(boolean isProvisionalLoad,
+            boolean isMainFrame, int errorCode, String description, String failingUrl) {
+        String unreachableWebDataUrl = AwContentsStatics.getUnreachableWebDataUrl();
+        boolean isErrorUrl =
+                unreachableWebDataUrl != null && unreachableWebDataUrl.equals(failingUrl);
+        if (isMainFrame && !isErrorUrl) {
+            if (errorCode != NetError.ERR_ABORTED) {
+                // This error code is generated for the following reasons:
+                // - WebView.stopLoading is called,
+                // - the navigation is intercepted by the embedder via shouldOverrideNavigation.
+                //
+                // The Android WebView does not notify the embedder of these situations using
+                // this error code with the WebViewClient.onReceivedError callback.
+                mAwContentsClient.onReceivedError(
+                        ErrorCodeConversionHelper.convertErrorCode(errorCode), description,
+                                failingUrl);
+            }
+            // Need to call onPageFinished after onReceivedError (if there is an error) for
+            // backwards compatibility with the classic webview.
+            mAwContentsClient.onPageFinished(failingUrl);
+        }
+    }
+
+    @Override
+    public void didNavigateMainFrame(String url, String baseUrl,
+            boolean isNavigationToDifferentPage, boolean isFragmentNavigation) {
+        // This is here to emulate the Classic WebView firing onPageFinished for main frame
+        // navigations where only the hash fragment changes.
+        if (isFragmentNavigation) {
+            mAwContentsClient.onPageFinished(url);
+        }
+    }
+
+    @Override
+    public void didNavigateAnyFrame(String url, String baseUrl, boolean isReload) {
+        mAwContentsClient.doUpdateVisitedHistory(url, isReload);
+    }
+}