Remove the "play-services-cronet" dependency in the example app when building `package:cronet_http_embedded` (#1103)

diff --git a/pkgs/cronet_http/tool/prepare_for_embedded.dart b/pkgs/cronet_http/tool/prepare_for_embedded.dart
index 3442bc6..aef0865 100644
--- a/pkgs/cronet_http/tool/prepare_for_embedded.dart
+++ b/pkgs/cronet_http/tool/prepare_for_embedded.dart
@@ -42,6 +42,14 @@
   'dl.google.com',
   'android/maven2/org/chromium/net/group-index.xml',
 );
+// Finds the Google Play Services Cronet dependency line. For example:
+// '    implementation "com.google.android.gms:play-services-cronet:18.0.1"'
+final implementationRegExp = RegExp(
+  '^\\s*implementation [\'"]'
+  '$_gmsDependencyName'
+  ':\\d+.\\d+.\\d+[\'"]',
+  multiLine: true,
+);
 
 void main(List<String> args) async {
   if (Directory.current.path.endsWith('tool')) {
@@ -51,7 +59,8 @@
   }
 
   final latestVersion = await _getLatestCronetVersion();
-  updateCronetDependency(latestVersion);
+  updateBuildGradle(latestVersion);
+  updateExampleBuildGradle();
   updatePubSpec();
   updateReadme();
   updateLibraryName();
@@ -75,22 +84,30 @@
 }
 
 /// Update android/build.gradle.
-void updateCronetDependency(String latestVersion) {
-  final fBuildGradle = File('${_packageDirectory.path}/android/build.gradle');
-  final gradleContent = fBuildGradle.readAsStringSync();
-  final implementationRegExp = RegExp(
-    '^\\s*implementation [\'"]'
-    '$_gmsDependencyName'
-    ':\\d+.\\d+.\\d+[\'"]',
-    multiLine: true,
-  );
+void updateBuildGradle(String latestVersion) {
+  final buildGradle = File('${_packageDirectory.path}/android/build.gradle');
+  final gradleContent = buildGradle.readAsStringSync();
   final newImplementation = '$_embeddedDependencyName:$latestVersion';
-  print('Patching $newImplementation');
+  print('Updating ${buildGradle.path}: adding $newImplementation');
   final newGradleContent = gradleContent.replaceAll(
     implementationRegExp,
     '    implementation "$newImplementation"',
   );
-  fBuildGradle.writeAsStringSync(newGradleContent);
+  buildGradle.writeAsStringSync(newGradleContent);
+}
+
+/// Remove the cronet reference from ./example/android/app/build.gradle.
+void updateExampleBuildGradle() {
+  final buildGradle =
+      File('${_packageDirectory.path}/example/android/app/build.gradle');
+  final gradleContent = buildGradle.readAsStringSync();
+
+  print('Updating ${buildGradle.path}: removing cronet reference');
+  final newGradleContent = gradleContent.replaceAll(
+    implementationRegExp,
+    '    // NOTE: removed in package:cronet_http_embedded',
+  );
+  buildGradle.writeAsStringSync(newGradleContent);
 }
 
 /// Update pubspec.yaml and example/pubspec.yaml.