prebuilt: initial Lawnchair prebuilt setup and build infrastructure

Initial Lawnchair prebuilt APK integration for PawletOS:
- Add priv-app/Lawnchair install target with Android.bp
- Add QuickstepSwitcherOverlay to override AOSP launcher
- Wire lawnchair.mk into product makefiles
- Add build_prebuilt.sh for Gradle -> prebuilt APK workflow
- Iteratively update from Lawnchair 2.1-alpha through 12 Alpha 5,
  12.1 Alpha 3, and 15 Beta 1 as upstream releases landed

README.md

@@ -1,22 +1,11 @@
-# Lawnchair AOSP based build system
+# Lawnchair Prebuilt
 
 ## Disclaimer
-- All credits go to the Lawnchair team.
-- Quickstep enablement is done with the help of QuickSwitch Magisk module made by [Skittles9823](https://github.com/skittles9823).
+- This repository is based on [arter97's android_vendor_lawnchair](https://github.com/arter97/android_vendor_lawnchair).  
+  It has been adapted from the original Android.mk format to the Android.bp build system.
 
-## Getting started
-**1. Add this repository to your AOSP build root's `vendor/lawnchair`**
+## Usage
+- Simply add the Lawnchair package to your `PRODUCT_PACKAGES`.
 
-**2. Import vendor/lawnchair/lawnchair.mk**
-
-In case of Paranoid Android, this can be done by appending the following at `vendor/pa/config/common.mk`:
-
-`$(call inherit-product-if-exists, vendor/lawnchair/lawnchair.mk)`
-
-**3. Remove existing launcher from the build**
-
-`ParanoidQuickStep`, `Launcher3QuickStep`, `PixelLauncher` and `TrebuchetQuickStep` packages are overriden from `priv-app/Lawnchair/Android.mk`.
-
-If your existing launcher uses a different name, either remove it from the build manually or post a pull-request.
-
-**4. Build Android**
+## Note
+- There is a QuickstepSwitcherOverlay still, but the current version of lawnchair does not support being the Quickstep launcher, it is kept for future use.

build_prebuilt.sh

@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+# Build a Lawnchair APK from source and place it here as a prebuilt.
+#
+# Usage:
+#   ./build_prebuilt.sh [path/to/apps_lawnchair]
+#
+# If no path is given, looks for apps_lawnchair as a sibling directory.
+# After running this, the APK still needs to be platform-signed before it
+# works as a privileged system app in a ROM build:
+#
+#   apksigner sign \
+#     --key   $ANDROID_BUILD_TOP/build/target/product/security/platform.pk8 \
+#     --cert  $ANDROID_BUILD_TOP/build/target/product/security/platform.x509.pem \
+#     priv-app/Lawnchair/Lawnchair.apk
+#
+# If you're only testing on a rooted device you can push the unsigned APK
+# directly and use pm to set it as the default launcher.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+SRC_DIR="${1:-$(dirname "$SCRIPT_DIR")/Lawnchair}"
+
+if [[ ! -f "$SRC_DIR/gradlew" ]]; then
+    echo "ERROR: Lawnchair source not found at: $SRC_DIR"
+    echo "Pass the path as the first argument: $0 /path/to/apps_lawnchair"
+    exit 1
+fi
+
+echo "==> Building Lawnchair from $SRC_DIR"
+cd "$SRC_DIR"
+./gradlew assembleLawnchairRelease --stacktrace
+
+APK=$(find . -name "*.apk" -path "*/lawnchair/release/*" | grep -v unsigned | head -1)
+if [[ -z "$APK" ]]; then
+    # Fallback: any release APK
+    APK=$(find . -name "*.apk" -path "*/release/*" | head -1)
+fi
+if [[ -z "$APK" ]]; then
+    echo "ERROR: No release APK found after Gradle build."
+    exit 1
+fi
+
+DEST="$SCRIPT_DIR/priv-app/Lawnchair/Lawnchair.apk"
+cp "$APK" "$DEST"
+echo ""
+echo "==> APK copied to: $DEST"
+echo ""
+echo "Next steps for AOSP ROM integration:"
+echo "  1. Sign with the platform key (see header comment in this script)"
+echo "  2. Commit the signed APK:  git -C '$SCRIPT_DIR' add priv-app/Lawnchair/Lawnchair.apk && git commit"
+echo "  3. Switch the manifest to prebuilt mode (see android_local_manifest/pawletos.xml)"
+echo ""
+echo "For direct device testing (root required):"
+echo "  adb push $DEST /system/priv-app/Lawnchair/Lawnchair.apk"
+echo "  adb shell am force-stop app.lawnchair"
+echo "  adb reboot"

etc/Android.bp

@@ -0,0 +1,15 @@
+prebuilt_etc {
+    name: "privapp-permissions-app.lawnchair.xml",
+    src: "permissions/privapp-permissions-app.lawnchair.xml",
+    sub_dir: "permissions",
+    filename_from_src: true,
+    installable: true,
+}
+
+prebuilt_etc {
+    name: "app.lawnchair-hiddenapi-package-whitelist.xml",
+    src: "sysconfig/app.lawnchair-hiddenapi-package-whitelist.xml",
+    sub_dir: "sysconfig",
+    filename_from_src: true,
+    installable: true,
+}

etc/permissions/privapp-permissions-app.lawnchair.xml

@@ -34,5 +34,9 @@
         <permission name="app.lawnchair.permission.READ_SETTINGS"/>
         <permission name="app.lawnchair.permission.WRITE_SETTINGS"/>
         <permission name="app.lawnchair.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION"/>
+        <permission name="android.permission.MANAGE_USERS"/>
+        <permission name="android.permission.ACCESS_HIDDEN_PROFILES_FULL"/>
+        <permission name="android.permission.INTERACT_ACROSS_USERS"/>
+        <permission name="android.permission.FORCE_STOP_PACKAGES"/>
     </privapp-permissions>
 </permissions>

lawnchair.mk

@@ -1,9 +0,0 @@
-include $(call first-makefiles-under,$(LOCAL_PATH))
-
-PRODUCT_COPY_FILES += \
-    vendor/lawnchair/etc/permissions/privapp-permissions-app.lawnchair.xml:$(TARGET_COPY_OUT_SYSTEM)/etc/permissions/privapp-permissions-app.lawnchair.xml \
-    vendor/lawnchair/etc/sysconfig/app.lawnchair-hiddenapi-package-whitelist.xml:$(TARGET_COPY_OUT_SYSTEM)/etc/sysconfig/app.lawnchair-hiddenapi-package-whitelist.xml \
-
-PRODUCT_PACKAGES += \
-    QuickstepSwitcherOverlay \
-    Lawnchair

priv-app/Lawnchair/Android.bp

@@ -0,0 +1,40 @@
+android_app_import {
+    name: "Lawnchair",
+    apk: "Lawnchair.apk",
+    privileged: true,
+    certificate: "platform",
+    overrides: [
+        "Launcher3",
+        "PixelLauncher",
+        "Trebuchet",
+    ],
+    required: [
+        "privapp-permissions-app.lawnchair.xml",
+        "app.lawnchair-hiddenapi-package-whitelist.xml",
+    ],
+    optional_uses_libs: [
+        "androidx.window.extensions",
+        "androidx.window.sidecar",
+    ],
+}
+
+// Include this alongside Lawnchair to also replace the QuickStep/recents
+// launcher (Launcher3QuickStep). Both modules reference the same APK;
+// the package manager deduplicates at install time.
+android_app_import {
+    name: "LawnchairQuickStep",
+    apk: "Lawnchair.apk",
+    privileged: true,
+    certificate: "platform",
+    overrides: [
+        "Launcher3QuickStep",
+    ],
+    required: [
+        "privapp-permissions-app.lawnchair.xml",
+        "app.lawnchair-hiddenapi-package-whitelist.xml",
+    ],
+    optional_uses_libs: [
+        "androidx.window.extensions",
+        "androidx.window.sidecar",
+    ],
+}

priv-app/Lawnchair/Android.mk

@@ -1,12 +0,0 @@
-LOCAL_PATH:= $(call my-dir)
-include $(CLEAR_VARS)
-
-LOCAL_MODULE := Lawnchair
-LOCAL_MODULE_STEM := Lawnchair.apk
-LOCAL_SRC_FILES := Lawnchair.apk
-LOCAL_MODULE_TAGS := optional
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT)/priv-app/Lawnchair
-LOCAL_OVERRIDES_PACKAGES := ParanoidQuickStep Launcher3QuickStep PixelLauncher TrebuchetQuickStep
-
-include $(BUILD_PREBUILT)

product/overlay/QuickstepSwitcherOverlay/Android.bp

@@ -0,0 +1,6 @@
+runtime_resource_overlay {
+    name: "Lawnchair-QuickstepSwitcherOverlay",
+    resource_dirs: ["res"],
+    sdk_version: "current",
+    product_specific: true,
+}

product/overlay/QuickstepSwitcherOverlay/Android.mk

@@ -1,15 +0,0 @@
-LOCAL_PATH:= $(call my-dir)
-include $(CLEAR_VARS)
-
-LOCAL_RRO_THEME := QuickstepSwitcher
-
-LOCAL_PRODUCT_MODULE := true
-
-LOCAL_SRC_FILES := $(call all-subdir-java-files)
-
-LOCAL_RESOURCE_DIR := $(LOCAL_PATH)/res
-
-LOCAL_PACKAGE_NAME := QuickstepSwitcherOverlay
-LOCAL_SDK_VERSION := current
-
-include $(BUILD_RRO_PACKAGE)