[Android WebView] Filter out error page URL from onPageFinished to un-flake tests

android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java

Index: android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java
diff --git a/android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java b/android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java
index b7c8ced1bf74146cc28d72f625455da8fb37ccbb..1d52ba8a638c231a767ca274ea83f4fab21a2384 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwContentsStatics.java
@@ -19,6 +19,8 @@ public class AwContentsStatics {
 
     private static ClientCertLookupTable sClientCertLookupTable;
 
+    private static String sUnreachableWebDataUrl;
+
     /**
      * Return the client certificate lookup table.
      */
@@ -61,10 +63,18 @@ public class AwContentsStatics {
         nativeSetDataReductionProxyEnabled(enabled);
     }
 
+    public static String getUnreachableWebDataUrl() {
+        if (sUnreachableWebDataUrl == null) {
+            sUnreachableWebDataUrl = nativeGetUnreachableWebDataUrl();
+        }
+        return sUnreachableWebDataUrl;
+    }
+
     //--------------------------------------------------------------------------------------------
     //  Native methods
     //--------------------------------------------------------------------------------------------
     private static native void nativeClearClientCertPreferences(Runnable callback);
     private static native void nativeSetDataReductionProxyKey(String key);
     private static native void nativeSetDataReductionProxyEnabled(boolean enabled);
+    private static native String nativeGetUnreachableWebDataUrl();
 }