Avoid unintended side-effects of loading javascript: URLS in Java Bridge tests

Change-Id: I8ba9a32ca0d0d80395029d92886155d2ed13d6f4

1 files changed, 6 insertions, 1 deletions

diff --git a/tests/WebViewTests/src/com/android/webviewtests/JavaBridgeTestBase.java b/tests/WebViewTests/src/com/android/webviewtests/JavaBridgeTestBase.java
index 1af3f63..a451015 100644
--- a/tests/WebViewTests/src/com/android/webviewtests/JavaBridgeTestBase.java
+++ b/tests/WebViewTests/src/com/android/webviewtests/JavaBridgeTestBase.java
@@ -106,7 +106,12 @@ public class JavaBridgeTestBase extends ActivityInstrumentationTestCase2<WebView
         runTestOnUiThread(new Runnable() {
             @Override
             public void run() {
-                getWebView().loadUrl("javascript:" + script);
+                // When a JavaScript URL is executed, if the value of the last
+                // expression evaluated is not 'undefined', this value is
+                // converted to a string and used as the new document for the
+                // frame. We don't want this behaviour, so wrap the script in
+                // an anonymous function.
+                getWebView().loadUrl("javascript:(function() { " + script + " })()");
             }
         });
     }