Get Gradle-built GmsCore unit tests closer to working

Change-Id: I7592bebb427c79b10170fef66fbf34c10e25e311
diff --git a/build.gradle b/build.gradle
new file mode 100644
index 0000000..51bb426
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,26 @@
+apply plugin: 'java'
+
+sourceSets {
+    main {
+        java {
+            srcDirs = [
+                'src/main/java',
+                'src/dx/java',
+                'src/mockito/java',
+            ]
+        }
+        resources {
+            srcDirs = ['src/mockito/resources']
+        }
+    }
+}
+
+jar {
+    baseName 'dexmaker'
+    classifier 'mockmaker'
+}
+
+dependencies {
+    compile getAndroidPrebuilt('10')
+    compile project(':mockito')
+}