build: bump minor dependencies versions

Change-Id: I8721fedb4dd1baa2dc8e0ed58c2780b19658af21
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 99aa73c..f6d38b0 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -50,7 +50,7 @@
 
 # Android SDK libraries, NDK
 ENV ANDROID_DEPS=\
-'build-tools;26.0.3 \
+'build-tools;27.0.3 \
  platforms;android-27 \
  extras;android;m2repository \
  extras;google;m2repository \
diff --git a/ring-android/app/build.gradle b/ring-android/app/build.gradle
index d36be08..bb91e13 100644
--- a/ring-android/app/build.gradle
+++ b/ring-android/app/build.gradle
@@ -4,7 +4,7 @@
 
 android {
     compileSdkVersion 27
-    buildToolsVersion "26.0.3"
+    buildToolsVersion '27.0.3'
 
     defaultConfig {
         minSdkVersion 18
@@ -36,6 +36,10 @@
         targetCompatibility JavaVersion.VERSION_1_8
     }
     buildTypes {
+        debug {
+            minifyEnabled true
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
         release {
             minifyEnabled true
             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
@@ -108,7 +112,7 @@
     implementation 'com.github.bumptech.glide:glide:3.8.0'
 
     // RxAndroid
-    implementation 'io.reactivex.rxjava2:rxandroid:2.0.1'
+    implementation 'io.reactivex.rxjava2:rxandroid:2.0.2'
 
     withFirebaseImplementation 'com.google.firebase:firebase-messaging:11.8.0'
 }
diff --git a/ring-android/build.gradle b/ring-android/build.gradle
index 0fd3ff6..0db9847 100644
--- a/ring-android/build.gradle
+++ b/ring-android/build.gradle
@@ -5,7 +5,7 @@
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:3.0.1'
-        classpath 'com.google.gms:google-services:3.1.0'
+        classpath 'com.google.gms:google-services:3.1.1'
     }
 }
 allprojects {
diff --git a/ring-android/libringclient/build.gradle b/ring-android/libringclient/build.gradle
index f34c4ee..9080c3e 100644
--- a/ring-android/libringclient/build.gradle
+++ b/ring-android/libringclient/build.gradle
@@ -12,7 +12,7 @@
     }
 
     // QRCode encoding
-    compile 'com.google.zxing:core:3.3.1'
+    compile 'com.google.zxing:core:3.3.2'
 
     // dependency injection
     compile 'javax.inject:javax.inject:1'
@@ -24,7 +24,7 @@
     testCompile 'junit:junit:4.12'
 
     // RxJava
-    compile "io.reactivex.rxjava2:rxjava:2.1.8"
+    compile "io.reactivex.rxjava2:rxjava:2.1.9"
 }
 
 sourceCompatibility = "1.7"