Apply multidex config in kotlin dsl gradle file (#114660)

* Apply multidex login in kotlin dsl gradle file

* Cleanup

* Remove plugin parameter passing

* Cleanup

* Restore dependencies block

* Analyzer

* Compiles

* Cleanup

* Cleanup

Author: GaryQian

packages/flutter_tools/gradle/flutter.gradle

@@ -237,15 +237,10 @@ class FlutterPlugin implements Plugin<Project> {
         flutterExecutable = Paths.get(flutterRoot.absolutePath, "bin", flutterExecutableName).toFile();
 
         if (project.hasProperty("multidex-enabled") &&
-            project.property("multidex-enabled").toBoolean() &&
-            project.android.defaultConfig.minSdkVersion <= 20) {
+            project.property("multidex-enabled").toBoolean()) {
             String flutterMultidexKeepfile = Paths.get(flutterRoot.absolutePath, "packages", "flutter_tools",
                 "gradle", "flutter_multidex_keepfile.txt")
             project.android {
-                defaultConfig {
-                    multiDexEnabled true
-                    manifestPlaceholders.applicationName = "io.flutter.app.FlutterMultiDexApplication"
-                }
                 buildTypes {
                     release {
                         multiDexKeepFile project.file(flutterMultidexKeepfile)
@@ -255,18 +250,9 @@ class FlutterPlugin implements Plugin<Project> {
             project.dependencies {
                 implementation "androidx.multidex:multidex:2.0.1"
             }
-        } else {
-            String baseApplicationName = "android.app.Application"
-            if (project.hasProperty("base-application-name")) {
-                baseApplicationName = project.property("base-application-name")
-            }
-            project.android {
-                defaultConfig {
-                    // Setting to android.app.Application is the same as omitting the attribute.
-                    manifestPlaceholders.applicationName = baseApplicationName
-                }
-            }
         }
+        // Use Kotlin DSL to handle baseApplicationName logic due to Groovy dynamic dispatch bug.
+        project.apply from: Paths.get(flutterRoot.absolutePath, "packages", "flutter_tools", "gradle", "flutter.gradle.kts")
 
         String flutterProguardRules = Paths.get(flutterRoot.absolutePath, "packages", "flutter_tools",
                 "gradle", "flutter_proguard_rules.pro")

packages/flutter_tools/gradle/flutter.gradle.kts

@@ -0,0 +1,33 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+apply<FlutterPluginKts>()
+
+class FlutterPluginKts : Plugin<Project> {
+    override fun apply(project: Project) {
+        // Use withGroovyBuilder and getProperty() to access Groovy metaprogramming.
+        project.withGroovyBuilder {
+            getProperty("android").withGroovyBuilder {
+                getProperty("defaultConfig").withGroovyBuilder {
+                    if (project.hasProperty("multidex-enabled") &&
+                        project.property("multidex-enabled").toString().toBoolean()) {
+                        setProperty("multiDexEnabled", true)
+                        getProperty("manifestPlaceholders").withGroovyBuilder {
+                            setProperty("applicationName", "io.flutter.app.FlutterMultiDexApplication")
+                        }
+                    } else {
+                        var baseApplicationName: String = "android.app.Application"
+                        if (project.hasProperty("base-application-name")) {
+                            baseApplicationName = project.property("base-application-name").toString()
+                        }
+                        // Setting to android.app.Application is the same as omitting the attribute.
+                        getProperty("manifestPlaceholders").withGroovyBuilder {
+                            setProperty("applicationName", baseApplicationName)
+                        }
+                    }
+                }
+            }
+        }
+    }
+}