title: Android app crashes after Signing
body: <pre><code>buildscript {
      repositories {
          maven { url 'https://maven.fabric.io/public' }
      }
  
      dependencies {
          classpath 'io.fabric.tools:gradle:1.+'
      }
  }
  apply plugin: 'com.android.application'
  apply plugin: 'io.fabric'
  
  repositories {
      maven { url 'https://maven.fabric.io/public' }
  }
  
  
  android {
      compileSdkVersion 22
      buildToolsVersion "22.0.1"
  
      defaultConfig {
          applicationId "com.android.hello"
          minSdkVersion 9
          targetSdkVersion 21
          compileOptions {
              sourceCompatibility JavaVersion.VERSION_1_7
              targetCompatibility JavaVersion.VERSION_1_7
          }
      }
  
      buildTypes {
          release {
              minifyEnabled true
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile 'com.android.support:support-v4:22.2.0'
      compile 'com.google.code.gson:gson:2.2.4'
      compile 'com.android.support:appcompat-v7:22.2.0'
      compile 'com.google.android.gms:play-services:+'
      compile files('libs/bolts-android-1.2.0.jar')
      compile files('libs/facebook.jar')
      compile 'de.hdodenhof:circleimageview:1.2.1'
      compile 'com.android.support:recyclerview-v7:21.0.+'
      compile 'com.android.support:cardview-v7:21.0.+'
      compile 'com.github.bumptech.glide:glide:3.5.2'
      compile 'com.android.support:support-v4:22.0.0'
      compile 'com.jakewharton:butterknife:6.1.0'
      compile('com.crashlytics.sdk.android:crashlytics:2.4.0@aar') {
          transitive = true;
      }
  
      compile project(':gcmv')
      compile 'com.android.support:design:22.2.0'
  }
  </code></pre>
  
  <p>when i signing my app app through a key with "minify true" in gradle it crashes after finishes.
  but when i set "minify false" it works fine after signing.
  so tell me is there any addition in the gradle file to release the with "minify true" property.
  For your reference i add the gradle file and my proguard file.</p>
  
  <pre><code># Add project specific ProGuard rules here.
  # By default, the flags in this file are appended to flags specified
  # in C:\Users\UMANH\AppData\Local\Android\sdk/tools/proguard/proguard-android.txt
  # You can edit the include path and order by changing the proguardFiles
  # directive in build.gradle.
  #
  # For more details, see
  #   http://developer.android.com/guide/developing/tools/proguard.html
  
  # Add any project specific keep options here:
  
  # If your project uses WebView with JS, uncomment the following
  # and specify the fully qualified class name to the JavaScript interface
  # class:
  #-keepclassmembers class fqcn.of.javascript.interface.for.webview {
  #   public *;
  #}
  -optimizations !code/simplification/arithmetic,!code/simplification/cast,!field/*,!class/merging/*
  -optimizationpasses 5
  -allowaccessmodification
  -dontpreverify
  
  # The remainder of this file is identical to the non-optimized version
  # of the Proguard configuration file (except that the other file has
  # flags to turn off optimization).
  
  -dontusemixedcaseclassnames
  -dontskipnonpubliclibraryclasses
  -verbose
  
  -keepattributes *Annotation*
  -keepattributes Signature
  -keep public class com.google.vending.licensing.ILicensingService
  -keep public class com.android.vending.licensing.ILicensingService
  
  # For native methods, see http://proguard.sourceforge.net/manual/examples.html#native
  -keepclasseswithmembernames class * {
      native &lt;methods&gt;;
  }
  
  # keep setters in Views so that animations can still work.
  # see http://proguard.sourceforge.net/manual/examples.html#beans
  -keepclassmembers public class * extends android.view.View {
     void set*(***);
     *** get*();
  }
  
  # We want to keep methods in Activity that could be used in the XML attribute onClick
  -keepclassmembers class * extends android.app.Activity {
     public void *(android.view.View);
  }
  
  # For enumeration classes, see http://proguard.sourceforge.net/manual/examples.html#enumerations
  -keepclassmembers enum * {
      public static **[] values();
      public static ** valueOf(java.lang.String);
  }
  
  -keep class * implements android.os.Parcelable {
    public static final android.os.Parcelable$Creator *;
  }
  
  -keepclassmembers class **.R$* {
      public static &lt;fields&gt;;
  }
  
  -keep class butterknife.** { *; }
  -dontwarn butterknife.internal.**
  -keep class **$$ViewBinder { *; }
  
  -keepclasseswithmembernames class * {
      @butterknife.* &lt;fields&gt;;
  }
  
  -keepclasseswithmembernames class * {
      @butterknife.* &lt;methods&gt;;
  }
  
  -keep public class * implements com.bumptech.glide.module.GlideModule
  -keep public enum com.bumptech.glide.load.resource.bitmap.ImageHeaderParser$** {
      **[] $VALUES;
      public *;
  }
  -keep public class android.support.v7.widget.** { *; }
  -keep public class android.support.v7.internal.widget.** { *; }
  -keep public class android.support.v7.internal.view.menu.** { *; }
  
  -keep class android.support.v4.app.** { *; }
  -keep interface android.support.v4.app.** { *; }
  
  -keep public class * extends android.support.v4.view.ActionProvider {
      public &lt;init&gt;(android.content.Context);
  }
  
  -keepattributes EnclosingMethod
  
  # Gson specific classes
  -keep class sun.misc.Unsafe { *; }
  -keep class com.google.gson.stream.** { *; }
  
  -keep class android.support.v7.widget.RoundRectDrawable { *; }
  
  -keepclassmembers class fqcn.of.javascript.interface.for.webview { public *;}
  
  -keep class com.crashlytics.** { *; }
  -dontwarn com.crashlytics.**
  
  -dontwarn android.support.design.**
  -keep class android.support.design.** { *; }
  -keep interface android.support.design.** { *; }
  -keep public class android.support.design.R$* { *; }
  
  -keep public class android.** {*;}
  -keep public class com.google.android.** {*;}
  
  
  -keep class com.facebook.** {*;}
  # The support library contains references to newer platform versions.
  # Don't warn about those in case this app is linking against an older
  # platform version.  We know about them, and they are safe.
  -dontwarn android.support.**
  -dontwarn com.facebook.**
  -dontwarn com.squareup.okhttp.**
  </code></pre>