--- a/mobile/android/app/build.gradle
+++ b/mobile/android/app/build.gradle
@@ -308,21 +308,17 @@ task checkstyle(type: Checkstyle) {
     // TODO: This ignores our pre-processed resources.
     include '**/*.java'
     // TODO: classpath should probably be something.
     classpath = files()
 }
 
 task syncPreprocessedCode(type: Sync, dependsOn: rootProject.generateCodeAndResources) {
     into("${project.buildDir}/generated/source/preprocessed_code")
-    from("${topobjdir}/mobile/android/base/generated/preprocessed") {
-        // All other preprocessed code is included in the geckoview project.
-        include '**/AdjustConstants.java'
-        include '**/MmaConstants.java'
-    }
+    from("${topobjdir}/mobile/android/base/generated/preprocessed")
 }
 
 // The localization system uses the moz.build preprocessor to interpolate a .dtd
 // file of XML entity definitions into an XML file of elements referencing those
 // entities.  (Each locale produces its own .dtd file, backstopped by the en-US
 // .dtd file in tree.)  Android Studio (and IntelliJ) don't handle these inline
 // entities smoothly.  This filter merely expands the entities in place, making
 // them appear properly throughout the IDE.  Be aware that this assumes that the

--- a/mobile/android/geckoview/build.gradle
+++ b/mobile/android/geckoview/build.gradle
@@ -139,46 +139,32 @@ android {
                     exclude 'org/mozilla/gecko/media/Utils.java'
                 }
 
                 if (mozconfig.substs.MOZ_WEBRTC) {
                     srcDir "${topsrcdir}/media/webrtc/trunk/webrtc/base/java/src"
                     srcDir "${topsrcdir}/media/webrtc/trunk/webrtc/modules/audio_device/android/java/src"
                     srcDir "${topsrcdir}/media/webrtc/trunk/webrtc/modules/video_capture/android/java/src"
                 }
-
-                // TODO: don't use AppConstants.
-                srcDir "${project.buildDir}/generated/source/preprocessed_code" // See syncPreprocessedCode.
             }
 
             assets {
             }
         }
     }
 }
 
 dependencies {
     compile "com.android.support:support-v4:${mozconfig.substs.ANDROID_SUPPORT_LIBRARY_VERSION}"
     compile "com.android.support:palette-v7:${mozconfig.substs.ANDROID_SUPPORT_LIBRARY_VERSION}"
 }
 
-task syncPreprocessedCode(type: Sync, dependsOn: rootProject.generateCodeAndResources) {
-    into("${project.buildDir}/generated/source/preprocessed_code")
-    from("${topobjdir}/mobile/android/base/generated/preprocessed") {
-        // These constants files are included in the main app project.
-        exclude '**/AdjustConstants.java'
-        exclude '**/MmaConstants.java'
-    }
-}
-
 apply from: "${topsrcdir}/mobile/android/gradle/with_gecko_binaries.gradle"
 
 android.libraryVariants.all { variant ->
-    variant.preBuild.dependsOn syncPreprocessedCode
-
     // Like 'debug', 'release', or 'withGeckoBinaries'.
     def buildType = variant.buildType.name
 
     // It would be most natural for :geckoview to always include the Gecko
     // binaries, but that's difficult; see the notes in
     // mobile/android/gradle/with_gecko_binaries.gradle.  Instead :app uses
     // :geckoview:release and handles it's own Gecko binary inclusion.
     if (buildType.equals('withGeckoBinaries')) {

--- a/mobile/android/geckoview/proguard-rules.txt
+++ b/mobile/android/geckoview/proguard-rules.txt
@@ -81,23 +81,16 @@
 # through introspection.
 
 -keepclassmembers class **.R$* {
   public static <fields>;
 }
 
 # GeckoView specific rules.
 
-# Keep classes, and all their contents, compiled before annotation.*.
--keep class org.mozilla.gecko.AppConstants {
-    *;
-}
--keep class org.mozilla.gecko.AppConstants$Versions {
-    *;
-}
 -keep class org.mozilla.gecko.SysInfo {
     *;
 }
 
 # Keep the annotation.
 -keep @interface org.mozilla.gecko.annotation.JNITarget
 
 # Keep classes tagged with the annotation.

--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
@@ -71,17 +71,16 @@ import android.hardware.SensorManager;
 import android.location.Criteria;
 import android.location.Location;
 import android.location.LocationListener;
 import android.location.LocationManager;
 import android.media.AudioManager;
 import android.net.ConnectivityManager;
 import android.net.NetworkInfo;
 import android.net.Uri;
-import android.os.Build;
 import android.os.Bundle;
 import android.os.Environment;
 import android.os.Looper;
 import android.os.ParcelFileDescriptor;
 import android.os.PowerManager;
 import android.os.SystemClock;
 import android.os.Vibrator;
 import android.provider.Settings;

--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/GeckoSurface.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/GeckoSurface.java
@@ -2,17 +2,16 @@
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 package org.mozilla.gecko.gfx;
 
 import android.graphics.SurfaceTexture;
 
-import android.os.Build;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.view.Surface;
 import android.util.Log;
 
 import java.util.HashMap;
 
 import org.mozilla.gecko.annotation.WrapForJNI;