Update from https://crrev.com/314320

base/test/android/javatests/src/org/chromium/base/test/BaseActivityInstrumentationTestCase.java

Index: base/test/android/javatests/src/org/chromium/base/test/BaseActivityInstrumentationTestCase.java
diff --git a/base/test/android/javatests/src/org/chromium/base/test/BaseActivityInstrumentationTestCase.java b/base/test/android/javatests/src/org/chromium/base/test/BaseActivityInstrumentationTestCase.java
new file mode 100644
index 0000000000000000000000000000000000000000..53dee4ab14594c4faeb99c8db7ff5be2e61e716c
--- /dev/null
+++ b/base/test/android/javatests/src/org/chromium/base/test/BaseActivityInstrumentationTestCase.java
@@ -0,0 +1,118 @@
+// Copyright 2015 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.base.test;
+
+import android.app.Activity;
+import android.content.Context;
+import android.os.SystemClock;
+import android.test.ActivityInstrumentationTestCase2;
+import android.util.Log;
+
+import org.chromium.base.BaseChromiumApplication;
+import org.chromium.base.CommandLine;
+import org.chromium.base.test.util.CommandLineFlags;
+
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Base class for all Activity-based Instrumentation tests.
+ *
+ * @param <T> The Activity type.
+ */
+public class BaseActivityInstrumentationTestCase<T extends Activity>
+        extends ActivityInstrumentationTestCase2<T> {
+
+    private static final String TAG = "BaseActivityInstrumentationTestCase";
+
+    private static final int SLEEP_INTERVAL = 50; // milliseconds
+    private static final int WAIT_DURATION = 5000; // milliseconds
+
+    /**
+     * Creates a instance for running tests against an Activity of the given class.
+     *
+     * @param activityClass The type of activity that will be tested.
+     */
+    public BaseActivityInstrumentationTestCase(Class<T> activityClass) {
+        super(activityClass);
+    }
+
+    /**
+     * Sets up the CommandLine with the appropriate flags.
+     *
+     * This will add the difference of the sets of flags specified by {@link CommandLineFlags.Add}
+     * and {@link CommandLineFlags.Remove} to the {@link org.chromium.base.CommandLine}. Note that
+     * trying to remove a flag set externally, i.e. by the command-line flags file, will not work.
+     */
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+
+        CommandLine.reset();
+        Context targetContext = getTargetContext();
+        assertNotNull("Unable to get a non-null target context.", targetContext);
+
+        BaseChromiumApplication.initCommandLine(targetContext);
+        Set<String> flags = getFlags(getClass().getMethod(getName()));
+        for (String flag : flags) {
+            CommandLine.getInstance().appendSwitch(flag);
+        }
+    }
+
+    /**
+     * Gets the target context.
+     *
+     * On older versions of Android, getTargetContext() may initially return null, so we have to
+     * wait for it to become available.
+     *
+     * @return The target {@link android.content.Context} if available; null otherwise.
+     */
+    private Context getTargetContext() {
+        Context targetContext = getInstrumentation().getTargetContext();
+        try {
+            long startTime = SystemClock.uptimeMillis();
+            // TODO(jbudorick): Convert this to CriteriaHelper once that moves to base/.
+            while (targetContext == null
+                    && SystemClock.uptimeMillis() - startTime < WAIT_DURATION) {
+                Thread.sleep(SLEEP_INTERVAL);
+                targetContext = getInstrumentation().getTargetContext();
+            }
+        } catch (InterruptedException e) {
+            Log.e(TAG, "Interrupted while attempting to initialize the command line.");
+        }
+        return targetContext;
+    }
+
+    private static Set<String> getFlags(AnnotatedElement element) {
+        AnnotatedElement parent = (element instanceof Method)
+                ? ((Method) element).getDeclaringClass()
+                : ((Class) element).getSuperclass();
+        Set<String> flags = (parent == null) ? new HashSet<String>() : getFlags(parent);
+
+        if (element.isAnnotationPresent(CommandLineFlags.Add.class)) {
+            flags.addAll(
+                    Arrays.asList(element.getAnnotation(CommandLineFlags.Add.class).value()));
+        }
+
+        if (element.isAnnotationPresent(CommandLineFlags.Remove.class)) {
+            List<String> flagsToRemove =
+                    Arrays.asList(element.getAnnotation(CommandLineFlags.Remove.class).value());
+            for (String flagToRemove : flagsToRemove) {
+                // If your test fails here, you have tried to remove a command-line flag via
+                // CommandLineFlags.Remove that was loaded into CommandLine via something other
+                // than CommandLineFlags.Add (probably the command-line flag file).
+                assertFalse("Unable to remove command-line flag \"" + flagToRemove + "\".",
+                        CommandLine.getInstance().hasSwitch(flagToRemove));
+            }
+            flags.removeAll(flagsToRemove);
+        }
+
+        return flags;
+    }
+}