Backed out changeset f5c4825b6ae8 (bug 1430417) for incorrect android:debuggable. r=nalexander

mobile/android/app/build.gradle

@@ -231,11 +231,11 @@ dependencies {
         implementation "com.google.android.gms:play-services-measurement:${mozconfig.substs.ANDROID_GOOGLE_PLAY_SERVICES_VERSION}"
     }
 
-    // Include LeakCanary in local builds, but not in official builds.  Mach
-    // builds target the official audience, so LeakCanary will not be included
-    // in any Mach build.
-    localImplementation 'com.squareup.leakcanary:leakcanary-android:1.4-beta1'
-    officialImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.4-beta1'
+    // Include LeakCanary in most gradle based builds.  Gradle based tests
+    // include the no-op version.  Mach based builds only include the no-op
+    // version of this library.
+    debugImplementation 'com.squareup.leakcanary:leakcanary-android:1.4-beta1'
+    releaseImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.4-beta1'
     testImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.4-beta1'
 
     implementation project(path: ':geckoview')