Fix loadUrl for javascript urls.

A recent update
https://codereview.chromium.org/1022993002
broke the loading of javascript URLs. This patch reverts only the part
of the update which is broken.

BUG=489259

Review URL: https://codereview.chromium.org/1131083004

Cr-Commit-Position: refs/heads/master@{#330507}

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

@@ -1301,8 +1301,7 @@ public class AwContents implements SmartClipProvider,
         if (url == null) {
             return;
         }
-        LoadUrlParams params = new LoadUrlParams(url);
-        loadUrl(params);
+        loadUrl(url, null);
     }
 
     /**