android-studio-preview: 3.0.0.10 -> 3.0.0.12

pkgs/applications/editors/android-studio/packages.nix

···
 
   preview = mkStudio rec {
     pname = "android-studio-preview";
-    version = "3.0.0.10"; # "Android Studio 3.0 Beta 2"
-    build = "171.4263559";
-    sha256Hash = "0bya69qa50s6dbvlzb198b5w6ixs21y6b56v3v1xjb3kndf9y44w";
+    version = "3.0.0.12"; # "Android Studio 3.0 Beta 4"
+    build = "171.4304935";
+    sha256Hash = "127ys250m1gdglj5y2qzxl73kh5qb4zlwyf79as7765mmcfcikn5";
 
     meta = stable.meta // {
       description = "The Official IDE for Android (preview version)";