title: Protobuf Android includes build type in generated folders
body: <p>I am using the following app.gradle to generate java classes from .proto classes inside an android sample project. </p>
  
  <pre><code>apply plugin: 'com.android.application'
  apply plugin: 'com.google.protobuf'
  android {
      compileSdkVersion 25
      buildToolsVersion "25.0.2"
      defaultConfig {
          applicationId "protobuf.example.com.protobuftestapp"
          minSdkVersion 21
          targetSdkVersion 25
          versionCode 1
          versionName "1.0"
          testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  protobuf {
      protoc {
          artifact = "com.google.protobuf:protoc:3.0.0"
      }
      plugins {
          lite {
              artifact = "com.google.protobuf:protoc-gen-javalite:3.0.0"
          }
      }
      generateProtoTasks {
          all().each { task -&gt;
              task.builtins {
                  remove java
              }
              task.plugins {
                  lite {
                      outputSubDir = ''
                  }
              }
          }
      }
      generatedFilesBaseDir = "$projectDir/src/main/java/"
  }
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
          exclude group: 'com.android.support', module: 'support-annotations'
      })
      compile 'com.android.support:appcompat-v7:25.3.1'
      compile 'com.android.support.constraint:constraint-layout:1.0.2'
      compile 'com.google.protobuf:protobuf-lite:3.0.0'
      testCompile 'junit:junit:4.12'
  }
  </code></pre>
  
  <p>The .proto file looks like this:</p>
  
  <pre><code>syntax = "proto3";
  package my_test_package;
  option java_package = "protoclasses";
  option java_outer_classname = "MyTestClass";
  message TestClass {
      string test_string_a = 1;
      int32 test_int_b = 2;
      bool test_bool_c = 3;
  }
  </code></pre>
  
  <p>The classes are generated, but the folder structure depends on the the buildType.</p>
  
  <p>The output is </p>
  
  <ul>
  <li>src->main->java-><strong>DEBUG</strong>->protoclasses->MyTestClass.java </li>
  <li>src->main->java-><strong>RELEASE</strong>->protoclasses->MyTestClass.java</li>
  </ul>
  
  <p>I searched for hours, but didn't manage to strip the buildType folder.
  The problem is, that the classes are generated as a duplicate, which leads to a failing build.</p>