Add MineDigger.apk that works offline

sky/sdk/example/BUILD.gn

Index: sky/sdk/example/BUILD.gn
diff --git a/examples/tiny/BUILD.gn b/sky/sdk/example/BUILD.gn
similarity index 57%
copy from examples/tiny/BUILD.gn
copy to sky/sdk/example/BUILD.gn
index 0a2c73a502ad066b538dedc49ae1bc42de41bc46..d8769a62a31ad6d7b69f78d0d81fc94fd9e5b080 100644
--- a/examples/tiny/BUILD.gn
+++ b/sky/sdk/example/BUILD.gn
@@ -2,10 +2,12 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//mojo/public/mojo_application.gni")
+group("example") {
+  testonly = true
 
-mojo_native_application("tiny") {
-  sources = [
-    "tiny.c",
-  ]
+  deps = []
+
+  if (is_android) {
+    deps += [ "//sky/sdk/example/mine_digger" ]
+  }
 }