Android camera fixes, purchase screen fixes

android/build.gradle

@@ -1,34 +1,33 @@
 buildscript {
-    repositories {
-        jcenter()
-        google()
-    }
+  ext.kotlin_version = '1.2.40'
+  repositories {
+    jcenter()
+    google()
+  }
 
-    dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.1'
-    }
+  dependencies {
+    classpath 'com.android.tools.build:gradle:3.1.1'
+    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+  }
 }
 
 allprojects {
-    repositories {
-        jcenter()
-        google()
-        maven {
-            url "https://maven.google.com"
-        }
-    }
+  repositories {
+    jcenter()
+    google()
+  }
 }
 
 rootProject.buildDir = '../build'
 subprojects {
-    project.buildDir = "${rootProject.buildDir}/${project.name}"
-    project.evaluationDependsOn(':app')
+  project.buildDir = "${rootProject.buildDir}/${project.name}"
+  project.evaluationDependsOn(':app')
 }
 
 task clean(type: Delete) {
-    delete rootProject.buildDir
+  delete rootProject.buildDir
 }
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '2.14.1'
+  gradleVersion = '2.14.1'
 }