Update gradle files

Change-Id: I7324082ef9eb19cb0851a0a53e8e41ee8f174210
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

src/3rdparty/gradle/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Mon Feb 20 10:43:22 EST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-3.4-bin.zip

src/3rdparty/gradle/gradlew

@@ -28,16 +28,16 @@ APP_NAME="Gradle"
 APP_BASE_NAME=`basename "$0"`
 
 # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS="-Xmx1024m -Dfile.encoding=UTF-8"
+DEFAULT_JVM_OPTS=""
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD="maximum"
 
-warn ( ) {
+warn () {
     echo "$*"
 }
 
-die ( ) {
+die () {
     echo
     echo "$*"
     echo
@@ -155,7 +155,7 @@ if $cygwin ; then
 fi
 
 # Escape application args
-save ( ) {
+save () {
     for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
     echo " "
 }

src/3rdparty/gradle/gradlew.bat

@@ -14,7 +14,7 @@ set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
 @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-set DEFAULT_JVM_OPTS=-Xmx1024m -Dfile.encoding=UTF-8
+set DEFAULT_JVM_OPTS=
 
 @rem Find java.exe
 if defined JAVA_HOME goto findJavaFromJavaHome

src/android/templates/build.gradle

@@ -1,17 +1,17 @@
 buildscript {
     repositories {
+        google()
         jcenter()
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.2.3'
+        classpath 'com.android.tools.build:gradle:3.0.1'
     }
 }
 
-allprojects {
-    repositories {
-        jcenter()
-    }
+repositories {
+    google()
+    jcenter()
 }
 
 apply plugin: 'com.android.application'