Fix build after updating from "compile" to "implementation"

See libgdx/libgdx#5491 (comment)

Author: agateau

build.gradle

@@ -131,15 +131,14 @@ project(":android") {
 }
 
 project(":core") {
-    apply plugin: "java"
-
+    apply plugin: "java-library"
 
     dependencies {
-        implementation "com.badlogicgames.gdx:gdx:$gdxVersion"
-        implementation "com.badlogicgames.gdx:gdx-box2d:$gdxVersion"
-        implementation "com.badlogicgames.gdx:gdx-freetype:$gdxVersion"
-        implementation "com.badlogicgames.gdx:gdx-controllers:$gdxVersion"
-        implementation "junit:junit:4.12"
-        implementation 'com.google.code.gson:gson:2.8.5'
+        api "com.badlogicgames.gdx:gdx:$gdxVersion"
+        api "com.badlogicgames.gdx:gdx-box2d:$gdxVersion"
+        api "com.badlogicgames.gdx:gdx-freetype:$gdxVersion"
+        api "com.badlogicgames.gdx:gdx-controllers:$gdxVersion"
+        api "junit:junit:4.12"
+        api 'com.google.code.gson:gson:2.8.5'
     }
 }

desktop/build.gradle

@@ -17,7 +17,7 @@ task run(dependsOn: classes, type: JavaExec) {
 task dist(type: Jar) {
     from files(sourceSets.main.output.classesDirs)
     from files(sourceSets.main.output.resourcesDir)
-    from {configurations.compile.collect {zipTree(it)}}
+    from {configurations.compileClasspath.collect { it.isDirectory() ? it : zipTree(it) }}
     from files(project.assetsDir)
 
     manifest {

tools/build.gradle

@@ -17,7 +17,7 @@ task run(dependsOn: classes, type: JavaExec) {
 task dist(type: Jar) {
     from files(sourceSets.main.output.classesDirs)
     from files(sourceSets.main.output.resourcesDir)
-    from {configurations.compile.collect {zipTree(it)}}
+    from {configurations.compileClasspath.collect { it.isDirectory() ? it : zipTree(it) }}
     from files(project.assetsDir)
 
     manifest {