Fixing various tests

> Migrating UI tests to AndroidJUnit4 for better support
> Removing obsolete RotationPreference test
> Fixing broken FileLogTest and AndroidJUnit4
> Removing InvariantDeviceProfileTest as it does not work well with
  resource overlays

Change-Id: I0abb1df6765d76d86c1c6c84e8ac35eb9a6bcdaa

tests/src/com/android/launcher3/util/rule/ShellCommandRule.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.android.launcher3.util.rule;
+
+import android.content.ComponentName;
+import android.content.pm.ActivityInfo;
+import android.os.ParcelFileDescriptor;
+import android.support.test.InstrumentationRegistry;
+
+import org.junit.rules.TestRule;
+import org.junit.runner.Description;
+import org.junit.runners.model.Statement;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+
+/**
+ * Test rule which executes a shell command at the start of the test.
+ */
+public class ShellCommandRule implements TestRule {
+
+    private final String mCmd;
+
+    public ShellCommandRule(String cmd) {
+        mCmd = cmd;
+    }
+
+    @Override
+    public Statement apply(Statement base, Description description) {
+        return new MyStatement(base, mCmd);
+    }
+
+    public static void runShellCommand(String command) throws IOException {
+        ParcelFileDescriptor pfd = InstrumentationRegistry.getInstrumentation().getUiAutomation()
+                .executeShellCommand(command);
+
+        // Read the input stream fully.
+        FileInputStream fis = new ParcelFileDescriptor.AutoCloseInputStream(pfd);
+        while (fis.read() != -1);
+        fis.close();
+    }
+
+    private static class MyStatement extends Statement {
+        private final Statement mBase;
+        private final String mCmd;
+
+        public MyStatement(Statement base, String cmd) {
+            mBase = base;
+            mCmd = cmd;
+        }
+
+        @Override
+        public void evaluate() throws Throwable {
+            runShellCommand(mCmd);
+            mBase.evaluate();
+        }
+    }
+
+    /**
+     * Grants the launcher permission to bind widgets.
+     */
+    public static ShellCommandRule grandWidgetBind() {
+        return new ShellCommandRule("appwidget grantbind --package "
+                + InstrumentationRegistry.getTargetContext().getPackageName());
+    }
+
+    /**
+     * Sets the target launcher as default launcher.
+     */
+    public static ShellCommandRule setDefaultLauncher() {
+        ActivityInfo launcher = InstrumentationRegistry.getTargetContext().getPackageManager()
+                .queryIntentActivities(LauncherActivityRule.getHomeIntent(), 0).get(0)
+                .activityInfo;
+        return new ShellCommandRule("cmd package set-home-activity " +
+                new ComponentName(launcher.packageName, launcher.name).flattenToString());
+    }
+}