title: I received an error on the first run of flutter project! `Finished with error: Gradle task assembleDebug failed with exit code 1`
body: <p>Today I started to learn flutter.</p>
  
  <p>I created new flutter project from <code>Flutter Application</code> in android studio 3.5.3.</p>
  
  <p>I created new android virtual device and then tried to run <code>main.dart</code>.</p>
  
  <p>I remember that my project freezed during initializing gradle in the first run so I had to stop and rerun <code>main.dart</code> and after that it raises following error:</p>
  
  <pre><code>Launching lib\main.dart on AOSP on IA Emulator in debug mode...
  Running Gradle task 'assembleDebug'...
  
  FAILURE: Build failed with an exception.
  
  * What went wrong:
  A problem occurred configuring root project 'android'.
  &gt; Could not resolve all artifacts for configuration ':classpath'.
     &gt; Could not find sdk-common.jar (com.android.tools:sdk-common:26.5.0).
       Searched in the following locations:
           https://dl.google.com/dl/android/maven2/com/android/tools/sdk-common/26.5.0/sdk-common-    26.5.0.jar
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
  
  * Get more help at https://help.gradle.org
  
  BUILD FAILED in 2s
  Finished with error: Gradle task assembleDebug failed with exit code 1
  </code></pre>
  
  <p><code>build.gradle</code> file contains:</p>
  
  <pre><code>buildscript {
      ext.kotlin_version = '1.3.50'
      repositories {
          google()
          jcenter()
      }
  
      dependencies {
          classpath 'com.android.tools.build:gradle:3.5.0'
          classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
      }
  }
  
  allprojects {
      repositories {
          google()
          jcenter()
      }
  }
  
  rootProject.buildDir = '../build'
  subprojects {
      project.buildDir = "${rootProject.buildDir}/${project.name}"
  }
  subprojects {
      project.evaluationDependsOn(':app')
  }
  
  task clean(type: Delete) {
      delete rootProject.buildDir
  }
  </code></pre>
  
  <p>and <code>settings.gradle</code> contains:</p>
  
  <pre><code>include ':app'
  
  def flutterProjectRoot = rootProject.projectDir.parentFile.toPath()
  
  def plugins = new Properties()
  def pluginsFile = new File(flutterProjectRoot.toFile(), '.flutter-plugins')
  if (pluginsFile.exists()) {
      pluginsFile.withReader('UTF-8') { reader -&gt; plugins.load(reader) }
  }
  
  plugins.each { name, path -&gt;
      def pluginDirectory = flutterProjectRoot.resolve(path).resolve('android').toFile()
      include ":$name"
      project(":$name").projectDir = pluginDirectory
  }
  </code></pre>
  
  <p>I guess that freezing was because of poor connection at the moment of initializing and <code>sdk-common.jar</code> didn`t download correctly.</p>
  
  <p>As I mentioned above, I'm new to flutter and I don't know how to clean build the project so I repeated step by step several times but error persists.</p>
  
  <p>I have no idea about this problem.
  Can anyone kindly help me?</p>
  
  <p>Please tell me if details are not clear enough to understand.</p>