[Android WebView] Implement a better OnReceivedError callback

android_webview/java/src/org/chromium/android_webview/AwContents.java

Index: android_webview/java/src/org/chromium/android_webview/AwContents.java
diff --git a/android_webview/java/src/org/chromium/android_webview/AwContents.java b/android_webview/java/src/org/chromium/android_webview/AwContents.java
index 8fa1b3393a2464daae33f58101e1dbe52930fc9e..b888cb2c2f8679aa288a9bf096764bddc6def2f6 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwContents.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwContents.java
@@ -62,6 +62,7 @@ import org.chromium.content_public.browser.WebContents;
 import org.chromium.content_public.browser.navigation_controller.LoadURLType;
 import org.chromium.content_public.browser.navigation_controller.UserAgentOverrideOption;
 import org.chromium.content_public.common.Referrer;
+import org.chromium.net.NetError;
 import org.chromium.ui.base.ActivityWindowAndroid;
 import org.chromium.ui.base.PageTransition;
 import org.chromium.ui.base.WindowAndroid;
@@ -419,6 +420,25 @@ public class AwContents implements SmartClipProvider,
         }
 
         @Override
+        public void onReceivedError(AwContentsClient.AwWebResourceRequest request,
+                AwContentsClient.AwWebResourceError error) {
+            String unreachableWebDataUrl = AwContentsStatics.getUnreachableWebDataUrl();

[sgurun-gerrit only, 2015/03/17 00:30:04]

maybe put a comment in getUnreachableWebDataUrl() that it is called from IO
thread. 

[mnaganov (inactive), 2015/03/17 15:29:09]

Good point. This may cause a race between two calls to
getUnreachableWebDataUrl() on IO and UI threads (as didFinishLoad also uses it),
but as they will be retrieving the same value, in the worst case, they will
retrieve it both simultaneously and update the cache variable one over another,
which should not harm anyone.

+            boolean isErrorUrl =
+                    unreachableWebDataUrl != null && unreachableWebDataUrl.equals(request.url);

[sgurun-gerrit only, 2015/03/17 00:30:04]

nit: is the indentation 8 chars here?

[mnaganov (inactive), 2015/03/17 15:29:09]

Hm. Yes -- it should be 8 as its a long line wrap, and "boolean " is 8 chars
long.

+            if (!isErrorUrl && error.errorCode != NetError.ERR_ABORTED) {
+                // NetError.ERR_ABORTED error code is generated for the following reasons:
+                // - WebView.stopLoading is called,
+                // - the navigation is intercepted by the embedder via shouldOverrideUrlLoading.
+                //
+                // Android WebView does not notify the embedder of these situations using
+                // this error code with the WebViewClient.onReceivedError callback.
+                error.errorCode = ErrorCodeConversionHelper.convertErrorCode(error.errorCode);
+                mContentsClient.getCallbackHelper().postOnReceivedError(request, error);
+            }
+            // AwWebContentsObserver.didFailLoad will send onPageFinished to the embedder.
+        }
+
+        @Override
         public void onReceivedHttpError(AwContentsClient.AwWebResourceRequest request,
                 AwWebResourceResponse response) {
             mContentsClient.getCallbackHelper().postOnReceivedHttpError(request, response);