Properly throw java exceptions from shouldOverrideUrlLoading

base/android/java/src/org/chromium/base/JavaHandlerThread.java

Index: base/android/java/src/org/chromium/base/JavaHandlerThread.java
diff --git a/base/android/java/src/org/chromium/base/JavaHandlerThread.java b/base/android/java/src/org/chromium/base/JavaHandlerThread.java
index cd057282b88513b4cc48d3d70b16978b9ac58849..43ef6fbe03f69d4e2e0a0d00ebfacb8e1bb1540e 100644
--- a/base/android/java/src/org/chromium/base/JavaHandlerThread.java
+++ b/base/android/java/src/org/chromium/base/JavaHandlerThread.java
@@ -40,6 +40,18 @@ class JavaHandlerThread {
         });
     }
 
+    @CalledByNative
+    private void startForTesting(
+            final long nativeThread, final long nativeEvent, final long nativeTestDoneEvent) {
+        mThread.start();
+        new Handler(mThread.getLooper()).post(new Runnable() {
+            @Override
+            public void run() {
+                nativeInitializeThreadForTesting(nativeThread, nativeEvent, nativeTestDoneEvent);
+            }
+        });
+    }
+
     @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
     @CalledByNative
     private void stop(final long nativeThread, final long nativeEvent) {
@@ -54,6 +66,23 @@ class JavaHandlerThread {
         if (quitSafely) mThread.quitSafely();
     }
 
+    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
+    @CalledByNative
+    private void stopForTesting(final long nativeThread, final long nativeEvent) {
+        final boolean quitSafely = Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2;
+        new Handler(mThread.getLooper()).post(new Runnable() {
+            @Override
+            public void run() {
+                nativeStopThreadForTesting(nativeThread, nativeEvent);
+                if (!quitSafely) mThread.quit();
+            }
+        });
+        if (quitSafely) mThread.quitSafely();
+    }
+
     private native void nativeInitializeThread(long nativeJavaHandlerThread, long nativeEvent);
+    private native void nativeInitializeThreadForTesting(
+            long nativeJavaHandlerThread, long nativeEvent, long nativeTestDoneEvent);
     private native void nativeStopThread(long nativeJavaHandlerThread, long nativeEvent);
+    private native void nativeStopThreadForTesting(long nativeJavaHandlerThread, long nativeEvent);
 }