Merge remote-tracking branch 'origin' into drawer.spring

CONTRIBUTING.md

+Contributing to Sky Engine
+==========================
+
+Getting the code
+----------------
+
+To get the code:
+
+ * Fork https://github.com/domokit/sky_engine into your own GitHub account.
+ * [Download depot_tools](http://www.chromium.org/developers/how-tos/install-depot-tools)
+   and make sure it is in your path.
+ * Create a `.gclient` file in an empty directory with the following contents:
+
+```
+solutions = [
+  {
+    "managed": False,
+    "name": "src",
+    "url": "git@github.com:<your_name_here>/sky_engine.git",
+    "custom_deps": {},
+    "deps_file": "DEPS",
+    "safesync_url": "",
+  },
+]
+target_os = ["android"]
+```
+
+ * `svn ls https://dart.googlecode.com/` and accept the certificate permanently.
+ * `gclient sync`
+ * `cd src`
+ * `git remote add upstream git@github.com:domokit/sky_engine.git`
+ * `./build/install-build-deps.sh`
+
+Building the code
+-----------------
+
+ * `./mojo/tools/mojob gn`
+ * `ninja -C out/Debug`
+
+Contributing code
+-----------------
+
+The Sky engine repository gladly accepts contributions via GitHub pull requests:
+
+ * `git fetch upstream`
+ * `git checkout upstream/master -b name_of_your_branch`
+ * Hack away
+ * `git commit -a`
+ * `git push origin name_of_your_branch`
+ * Go to `https://github.com/<your_name_here>/sky_engine` and click the
+   "Compare & pull request" button