Upgrade dependency versions

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=171819854

build.gradle

@@ -17,7 +17,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.0-beta5'
+        classpath 'com.android.tools.build:gradle:3.0.0-beta7'
         classpath 'com.novoda:bintray-release:0.5.0'
     }
     // Workaround for the following test coverage issue. Remove when fixed:

constants.gradle

@@ -19,10 +19,10 @@ project.ext {
     minSdkVersion = 14
     compileSdkVersion = 26
     targetSdkVersion = 26
-    buildToolsVersion = '26'
+    buildToolsVersion = '26.0.2'
     testSupportLibraryVersion = '0.5'
-    supportLibraryVersion = '26.0.2'
-    playServicesLibraryVersion = '11.2.0'
+    supportLibraryVersion = '26.1.0'
+    playServicesLibraryVersion = '11.4.2'
     dexmakerVersion = '1.2'
     mockitoVersion = '1.9.5'
     junitVersion = '4.12'