[Android WebView] Propagate Java exceptions from JS dialog callbacks

android_webview/java/src/org/chromium/android_webview/AwContentsClientBridge.java

 // Copyright 2013 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 android.content.Context;
 import android.net.http.SslCertificate;
 import android.net.http.SslError;
+import android.os.Handler;
 import android.util.Log;
 import android.webkit.ValueCallback;
 
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.CalledByNativeUnchecked;
 import org.chromium.base.annotations.JNINamespace;
 import org.chromium.net.NetError;
 
 import java.security.Principal;
@@ skipping 204 matching lines @@
             }
 
         }
 
         final ClientCertificateRequestCallback callback =
                 new ClientCertificateRequestCallback(id, host, port);
         mClient.onReceivedClientCertRequest(callback, keyTypes, principals, host, port);
     }
 
     @CalledByNative
-    private void handleJsAlert(String url, String message, int id) {
-        JsResultHandler handler = new JsResultHandler(this, id);
-        mClient.handleJsAlert(url, message, handler);
+    private void handleJsAlert(final String url, final String message, final int id) {
+        // Post the application callback back to the current thread to ensure the application
+        // callback is executed without any native code on the stack. This so that any exception
+        // thrown by the application callback won't have to be propagated through a native call
+        // stack.
+        new Handler().post(new Runnable() {
+            @Override
+            public void run() {
+                JsResultHandler handler = new JsResultHandler(AwContentsClientBridge.this, id);
+                mClient.handleJsAlert(url, message, handler);
+            }
+        });
     }
 
     @CalledByNative
-    private void handleJsConfirm(String url, String message, int id) {
-        JsResultHandler handler = new JsResultHandler(this, id);
-        mClient.handleJsConfirm(url, message, handler);
+    private void handleJsConfirm(final String url, final String message, final int id) {
+        // Post the application callback back to the current thread to ensure the application
+        // callback is executed without any native code on the stack. This so that any exception
+        // thrown by the application callback won't have to be propagated through a native call
+        // stack.
+        new Handler().post(new Runnable() {
+            @Override
+            public void run() {
+                JsResultHandler handler = new JsResultHandler(AwContentsClientBridge.this, id);
+                mClient.handleJsConfirm(url, message, handler);
+            }
+        });
     }
 
     @CalledByNative
-    private void handleJsPrompt(String url, String message, String defaultValue, int id) {
-        JsResultHandler handler = new JsResultHandler(this, id);
-        mClient.handleJsPrompt(url, message, defaultValue, handler);
+    private void handleJsPrompt(
+            final String url, final String message, final String defaultValue, final int id) {
+        // Post the application callback back to the current thread to ensure the application
+        // callback is executed without any native code on the stack. This so that any exception
+        // thrown by the application callback won't have to be propagated through a native call
+        // stack.
+        new Handler().post(new Runnable() {
+            @Override
+            public void run() {
+                JsResultHandler handler = new JsResultHandler(AwContentsClientBridge.this, id);
+                mClient.handleJsPrompt(url, message, defaultValue, handler);
+            }
+        });
     }
 
     @CalledByNative
     private void handleJsBeforeUnload(String url, String message, int id) {
         JsResultHandler handler = new JsResultHandler(this, id);
         mClient.handleJsBeforeUnload(url, message, handler);
     }
 
     @CalledByNative
     private void newDownload(String url, String userAgent, String contentDisposition,
@@ skipping 109 matching lines @@
     //--------------------------------------------------------------------------------------------
     private native void nativeProceedSslError(long nativeAwContentsClientBridge, boolean proceed,
             int id);
     private native void nativeProvideClientCertificateResponse(long nativeAwContentsClientBridge,
             int id, byte[][] certChain, PrivateKey androidKey);
 
     private native void nativeConfirmJsResult(long nativeAwContentsClientBridge, int id,
             String prompt);
     private native void nativeCancelJsResult(long nativeAwContentsClientBridge, int id);
 }