Add SplitScreenUtils#enterSplitViaIntent for FlickerTests

As SplitScreenUtils#enterSplit uses UiAutomation to enter split-screen
with UI operations, which may flaky if the UI component or position
changed, or the test doesn't requires to verify entering split-screen
with drag-and-drop or clicking the menu on the overview.
(e.g. UnlockKeyguardToSplitScreen)

Added the new helper method to enter split-screen mode with using
EXTRA_LAUNCH_ADJACENT for SplitScreenPrimaryActivity to launch
SplitScreenSecondaryActivity in adjacent side.

Fix: 284175072
Test: atest WMShellFlickerTests:UnlockKeyguardToSplitScreen \
         --rerun-until-failure 10
Change-Id: Ic34007b0fe922bec0cef0a7b2a1bfd80cbea5776

libs/WindowManager/Shell/tests/flicker/src/com/android/wm/shell/flicker/splitscreen/SplitScreenUtils.kt

@@ -39,6 +39,7 @@ import com.android.server.wm.flicker.helpers.NonResizeableAppHelper
 import com.android.server.wm.flicker.helpers.NotificationAppHelper
 import com.android.server.wm.flicker.helpers.SimpleAppHelper
 import com.android.server.wm.flicker.testapp.ActivityOptions
+import com.android.server.wm.flicker.testapp.ActivityOptions.SplitScreen.Primary
 import com.android.wm.shell.flicker.LAUNCHER_UI_PACKAGE_NAME
 import com.android.wm.shell.flicker.SYSTEM_UI_PACKAGE_NAME
 import org.junit.Assert.assertNotNull
@@ -112,6 +113,17 @@ internal object SplitScreenUtils {
         waitForSplitComplete(wmHelper, primaryApp, secondaryApp)
     }
 
+    fun enterSplitViaIntent(
+            wmHelper: WindowManagerStateHelper,
+            primaryApp: StandardAppHelper,
+            secondaryApp: StandardAppHelper
+    ) {
+        val stringExtras = mapOf(Primary.EXTRA_LAUNCH_ADJACENT to "true")
+        primaryApp.launchViaIntent(wmHelper, null, null,
+                stringExtras)
+        waitForSplitComplete(wmHelper, primaryApp, secondaryApp)
+    }
+
     fun splitFromOverview(tapl: LauncherInstrumentation, device: UiDevice) {
         // Note: The initial split position in landscape is different between tablet and phone.
         // In landscape, tablet will let the first app split to right side, and phone will

libs/WindowManager/Shell/tests/flicker/src/com/android/wm/shell/flicker/splitscreen/UnlockKeyguardToSplitScreen.kt

@@ -51,7 +51,6 @@ class UnlockKeyguardToSplitScreen(override val flicker: FlickerTest) :
     /** {@inheritDoc} */
     override val transition: FlickerBuilder.() -> Unit
         get() = {
-            defaultSetup(this)
             defaultTeardown(this)
             thisTransition(this)
         }

libs/WindowManager/Shell/tests/flicker/src/com/android/wm/shell/flicker/splitscreen/benchmark/UnlockKeyguardToSplitScreenBenchmark.kt

@@ -37,7 +37,7 @@ open class UnlockKeyguardToSplitScreenBenchmark(override val flicker: FlickerTes
         SplitScreenBase(flicker) {
     protected val thisTransition: FlickerBuilder.() -> Unit
         get() = {
-            setup { SplitScreenUtils.enterSplit(wmHelper, tapl, device, primaryApp, secondaryApp) }
+            setup { SplitScreenUtils.enterSplitViaIntent(wmHelper, primaryApp, secondaryApp) }
             transitions {
                 device.sleep()
                 wmHelper.StateSyncBuilder().withAppTransitionIdle().waitForAndVerify()

tests/FlickerTests/test-apps/flickerapp/src/com/android/server/wm/flicker/testapp/ActivityOptions.java

@@ -186,6 +186,8 @@ public class ActivityOptions {
             public static final String LABEL = "SplitScreenPrimaryActivity";
             public static final ComponentName COMPONENT = new ComponentName(FLICKER_APP_PACKAGE,
                     FLICKER_APP_PACKAGE + ".SplitScreenActivity");
+
+            public static final String EXTRA_LAUNCH_ADJACENT = "launch_adjacent";
         }
 
         public static class Secondary {

tests/FlickerTests/test-apps/flickerapp/src/com/android/server/wm/flicker/testapp/SplitScreenActivity.java

@@ -16,9 +16,14 @@
 
 package com.android.server.wm.flicker.testapp;
 
+import static com.android.server.wm.flicker.testapp.ActivityOptions.SplitScreen.Primary.EXTRA_LAUNCH_ADJACENT;
+
 import android.app.Activity;
+import android.content.Intent;
 import android.os.Bundle;
 
+import androidx.annotation.Nullable;
+
 public class SplitScreenActivity extends Activity {
 
     @Override
@@ -26,4 +31,17 @@ public class SplitScreenActivity extends Activity {
         super.onCreate(icicle);
         setContentView(R.layout.activity_splitscreen);
     }
+
+    @Override
+    protected void onPostCreate(@Nullable Bundle savedInstanceState) {
+        super.onPostCreate(savedInstanceState);
+        final boolean startSecondaryActivity = getIntent().hasExtra(EXTRA_LAUNCH_ADJACENT);
+        if (startSecondaryActivity) {
+            final Intent intent = new Intent(this, SplitScreenSecondaryActivity.class);
+            intent.addCategory(Intent.CATEGORY_LAUNCHER);
+            intent.addFlags(Intent.FLAG_ACTIVITY_LAUNCH_ADJACENT | Intent.FLAG_ACTIVITY_NEW_TASK
+                    | Intent.FLAG_ACTIVITY_MULTIPLE_TASK);
+            startActivity(intent);
+        }
+    }
 }