I solved the problem by moving:
maven {
url 'https://dl.google.com/dl/android/maven2'
}
in the top of:
jcenter()
in the file: .flutter/packages/flutter_tools/gradle/flutter.gradle
:
buildscript {
repositories {
maven {
url 'https://dl.google.com/dl/android/maven2'
}
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.1.2'
}
}