Add TestRules for content shell test and refactor test bases

content/public/test/android/javatests/src/org/chromium/content/browser/test/NativeLibraryTestRule.java

Index: content/public/test/android/javatests/src/org/chromium/content/browser/test/NativeLibraryTestRule.java
diff --git a/content/public/test/android/javatests/src/org/chromium/content/browser/test/NativeLibraryTestRule.java b/content/public/test/android/javatests/src/org/chromium/content/browser/test/NativeLibraryTestRule.java
new file mode 100644
index 0000000000000000000000000000000000000000..1018d95196f8702428c07382d376bdb6155696f6
--- /dev/null
+++ b/content/public/test/android/javatests/src/org/chromium/content/browser/test/NativeLibraryTestRule.java
@@ -0,0 +1,43 @@
+// Copyright 2017 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.content.browser.test;
+
+import android.support.test.InstrumentationRegistry;
+
+import org.junit.rules.TestRule;
+import org.junit.runner.Description;
+import org.junit.runners.model.Statement;
+
+/**
+ * TestRule that adds support for loading and dealing with native libraries.
+ */
+public class NativeLibraryTestRule implements TestRule {

[boliu, 2017/03/08 21:40:18]

why does this not inherit from android base class? whatever the explanation,
probably worth a comment?

[the real yoland, 2017/03/08 22:53:53]

Done

+    private final NativeLibraryTestCommon mTestCommon = new NativeLibraryTestCommon();
+
+    /**
+     * Loads the native library on the activity UI thread (must not be called from the UI thread).
+     */
+    public void loadNativeLibraryNoBrowserProcess() {
+        mTestCommon.handleNativeInitialization(false, InstrumentationRegistry.getInstrumentation());
+    }
+
+    /**
+     * Loads the native library on the activity UI thread (must not be called from the UI thread).
+     * After loading the library, this will initialize the browser process.
+     */
+    public void loadNativeLibraryAndInitBrowserProcess() {
+        mTestCommon.handleNativeInitialization(true, InstrumentationRegistry.getInstrumentation());
+    }
+
+    @Override
+    public Statement apply(final Statement base, Description description) {

[boliu, 2017/03/08 21:40:18]

just return base?

[the real yoland, 2017/03/08 22:53:53]

Oops, done

+        return new Statement() {
+            @Override
+            public void evaluate() throws Throwable {
+                base.evaluate();
+            }
+        };
+    }
+}