[WIP] Updated applying gradle plugin for flutter_plugin_android_lifec…

…ycles (flutter#7786)

Updated applying gradle plugins to usage of declarative blocks.
Intending on updating all android example apps under packages. Did one
as a proof of concept before doing more.

Fixes partially
[#152656](flutter/flutter#152656)

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- [x] The title of the PR starts with the name of the package surrounded
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- [x] I [linked to at least one issue that this PR fixes] in the
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- [x] I updated `pubspec.yaml` with an appropriate new version according
to the [pub versioning philosophy], or this PR is [exempt from version
changes].
- [x] I updated `CHANGELOG.md` to add a description of the change,
[following repository CHANGELOG style], or this PR is [exempt from
CHANGELOG changes].
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] All existing and new tests are passing.

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https://github.com/flutter/flutter/blob/master/docs/contributing/Tree-hygiene.md
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packages/flutter_plugin_android_lifecycle/example/android/app/build.gradle

@@ -1,3 +1,9 @@
+plugins {
+    id "com.android.application"
+    id "dev.flutter.flutter-gradle-plugin"
+    id "com.google.cloud.artifactregistry.gradle-plugin"
+}
+
 def localProperties = new Properties()
 def localPropertiesFile = rootProject.file('local.properties')
 if (localPropertiesFile.exists()) {
@@ -6,11 +12,6 @@ if (localPropertiesFile.exists()) {
     }
 }
 
-def flutterRoot = localProperties.getProperty('flutter.sdk')
-if (flutterRoot == null) {
-    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
-}
-
 def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
 if (flutterVersionCode == null) {
     flutterVersionCode = '1'
@@ -21,8 +22,6 @@ if (flutterVersionName == null) {
     flutterVersionName = '1.0'
 }
 
-apply plugin: 'com.android.application'
-apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
     compileSdk flutter.compileSdkVersion

packages/flutter_plugin_android_lifecycle/example/android/build.gradle

@@ -1,14 +1,3 @@
-buildscript {
-    repositories {
-        google()
-        mavenCentral()
-    }
-
-    dependencies {
-        classpath 'com.android.tools.build:gradle:8.5.1'
-    }
-}
-
 allprojects {
     repositories {
         // See https://github.com/flutter/flutter/blob/master/docs/ecosystem/Plugins-and-Packages-repository-structure.md#gradle-structure for more info.

packages/flutter_plugin_android_lifecycle/example/android/settings.gradle

@@ -1,28 +1,37 @@
-include ':app'
+pluginManagement {
+    def flutterSdkPath = {
+        def properties = new Properties()
+        file("local.properties").withInputStream { properties.load(it) }
+        def flutterSdkPath = properties.getProperty("flutter.sdk")
+        assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
+        return flutterSdkPath
+    }()
 
-def flutterProjectRoot = rootProject.projectDir.parentFile.toPath()
+    includeBuild("$flutterSdkPath/packages/flutter_tools/gradle")
 
-def plugins = new Properties()
-def pluginsFile = new File(flutterProjectRoot.toFile(), '.flutter-plugins')
-if (pluginsFile.exists()) {
-    pluginsFile.withReader('UTF-8') { reader -> plugins.load(reader) }
-}
-
-plugins.each { name, path ->
-    def pluginDirectory = flutterProjectRoot.resolve(path).resolve('android').toFile()
-    include ":$name"
-    project(":$name").projectDir = pluginDirectory
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
 }
 
 // See https://github.com/flutter/flutter/blob/master/docs/ecosystem/Plugins-and-Packages-repository-structure.md#gradle-structure for more info.
 buildscript {
-  repositories {
-    maven {
-      url "https://plugins.gradle.org/m2/"
+    repositories {
+        maven {
+            url "https://plugins.gradle.org/m2/"
+        }
+    }
+    dependencies {
+        classpath "gradle.plugin.com.google.cloud.artifactregistry:artifactregistry-gradle-plugin:2.2.1"
     }
-  }
-  dependencies {
-    classpath "gradle.plugin.com.google.cloud.artifactregistry:artifactregistry-gradle-plugin:2.2.1"
-  }
+}
+
+plugins {
+    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
+    id "com.android.application" version "8.1.0" apply false
 }
 apply plugin: "com.google.cloud.artifactregistry.gradle-plugin"
+
+include ":app"