Bug 1405081 - Move GeckoSessionTestRule.waitForResult() into UiThreadUtils r=jchen

Differential Revision: https://phabricator.services.mozilla.com/D7798

mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/rule/GeckoSessionTestRule.java

@@ -2243,46 +2243,14 @@ public class GeckoSessionTestRule implements TestRule {
      * @param <T> The type of the value held by the {@link GeckoResult}
      * @return The value of the completed {@link GeckoResult}.
      */
-    public <T> T waitForResult(@NonNull GeckoResult<T> result) {
-        final ResultHolder<T> holder = new ResultHolder<>(result);
-
+    public <T> T waitForResult(@NonNull GeckoResult<T> result) throws Throwable {
+        beforeWait();
         try {
-            beforeWait();
-            while (!holder.isComplete) {
-                UiThreadUtils.loopUntilIdle(mTimeoutMillis);
-            }
+            return UiThreadUtils.waitForResult(result, mTimeoutMillis);
+        } catch (final Throwable e) {
+            throw unwrapRuntimeException(e);
         } finally {
             afterWait(mCallRecords.size());
         }
-
-        if (holder.error != null) {
-            throw unwrapRuntimeException(holder.error);
-        }
-
-        return holder.value;
-    }
-
-    private static class ResultHolder<T> {
-        public T value;
-        public Throwable error;
-        public boolean isComplete;
-
-        public ResultHolder(GeckoResult<T> result) {
-            result.then(new OnValueListener<T, Void>() {
-                @Override
-                public GeckoResult<Void> onValue(T value) {
-                    ResultHolder.this.value = value;
-                    isComplete = true;
-                    return null;
-                }
-            }, new OnExceptionListener<Void>() {
-                @Override
-                public GeckoResult<Void> onException(Throwable error) {
-                    ResultHolder.this.error = error;
-                    isComplete = true;
-                    return null;
-                }
-            });
-        }
     }
 }

mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/util/UiThreadUtils.java

@@ -1,10 +1,18 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 package org.mozilla.geckoview.test.util;
 
+import org.mozilla.geckoview.GeckoResult;
+
 import android.os.Handler;
 import android.os.Looper;
 import android.os.Message;
 import android.os.MessageQueue;
 import android.os.SystemClock;
+import android.support.annotation.NonNull;
 import android.util.Log;
 
 import java.lang.reflect.InvocationTargetException;
@@ -72,6 +80,52 @@ public class UiThreadUtils {
         return new RuntimeException(cause != null ? cause : e);
     }
 
+    /**
+     * This waits for the given result and returns it's value. If
+     * the result failed with an exception, it is rethrown.
+     *
+     * @param result A {@link GeckoResult} instance.
+     * @param <T> The type of the value held by the {@link GeckoResult}
+     * @return The value of the completed {@link GeckoResult}.
+     */
+    public static <T> T waitForResult(@NonNull GeckoResult<T> result, long timeout) throws Throwable {
+        final ResultHolder<T> holder = new ResultHolder<>(result);
+
+        while (!holder.isComplete) {
+            loopUntilIdle(timeout);
+        }
+
+        if (holder.error != null) {
+            throw holder.error;
+        }
+
+        return holder.value;
+    }
+
+    private static class ResultHolder<T> {
+        public T value;
+        public Throwable error;
+        public boolean isComplete;
+
+        public ResultHolder(GeckoResult<T> result) {
+            result.then(new GeckoResult.OnValueListener<T, Void>() {
+                @Override
+                public GeckoResult<Void> onValue(T value) {
+                    ResultHolder.this.value = value;
+                    isComplete = true;
+                    return null;
+                }
+            }, new GeckoResult.OnExceptionListener<Void>() {
+                @Override
+                public GeckoResult<Void> onException(Throwable error) {
+                    ResultHolder.this.error = error;
+                    isComplete = true;
+                    return null;
+                }
+            });
+        }
+    }
+
     public static void loopUntilIdle(final long timeout) {
         // Adapted from GeckoThread.pumpMessageLoop.
         final MessageQueue queue = HANDLER.getLooper().getQueue();