[Android WebView] Provide a minimal error description for nav errors

Since not all net error codes can be mapped onto Android error codes,
at least provide a minimal description for the client.

Review URL: https://chromiumcodereview.appspot.com/15979017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@204002 0039d316-1c4b-4281-b951-d872f2087c98

android_webview/javatests/src/org/chromium/android_webview/test/ClientOnReceivedErrorTest.java

@@ -5,6 +5,7 @@
 package org.chromium.android_webview.test;
 
 import android.test.suitebuilder.annotation.MediumTest;
+import android.webkit.WebSettings;
 
 import org.chromium.android_webview.AwContents;
 import org.chromium.android_webview.AndroidProtocolHandler;
@@ -118,4 +119,21 @@ public class ClientOnReceivedErrorTest extends AwTestBase {
         assertEquals(url, onReceivedErrorHelper.getFailingUrl());
         assertNotNull(onReceivedErrorHelper.getDescription());
     }
+
+    @MediumTest
+    @Feature({"AndroidWebView"})
+    public void testCacheMiss() throws Throwable {
+        TestCallbackHelperContainer.OnReceivedErrorHelper onReceivedErrorHelper =
+                mContentsClient.getOnReceivedErrorHelper();
+        final String url = "http://example.com/index.html";
+        int onReceivedErrorCallCount = onReceivedErrorHelper.getCallCount();
+        getAwSettingsOnUiThread(mAwContents).setCacheMode(WebSettings.LOAD_CACHE_ONLY);
+        loadUrlAsync(mAwContents, url);
+
+        onReceivedErrorHelper.waitForCallback(onReceivedErrorCallCount);
+        assertEquals(ErrorCodeConversionHelper.ERROR_UNKNOWN,
+                     onReceivedErrorHelper.getErrorCode());
+        assertEquals(url, onReceivedErrorHelper.getFailingUrl());
+        assertNotNull(onReceivedErrorHelper.getDescription());
+    }
 }

android_webview/renderer/aw_content_renderer_client.cc

@@ -13,6 +13,7 @@
 #include "components/visitedlink/renderer/visitedlink_slave.h"
 #include "content/public/renderer/render_thread.h"
 #include "googleurl/src/gurl.h"
+#include "net/base/net_errors.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/WebURL.h"
 #include "third_party/WebKit/public/platform/WebURLError.h"
@@ -68,9 +69,13 @@ void AwContentRendererClient::GetNavigationErrorStrings(
     std::string contents;
     if (err.empty()) {
       contents = AwResource::GetNoDomainPageContent();
+      if (error_description)
+        *error_description = ASCIIToUTF16(net::ErrorToString(error.reason));
     } else {
       contents = AwResource::GetLoadErrorPageContent();
       ReplaceSubstringsAfterOffset(&contents, 0, "%e", err);
+      if (error_description)
+        *error_description = error.localizedDescription;
     }
 
     ReplaceSubstringsAfterOffset(&contents, 0, "%s",