Auto merge of #8891 - mbrubeck:mach-install, r=larsbergstrom

Android build system improvements

This PR adds a `mach install` command (a convenient way to run `adb install`), and does some minor code cleanup.

It also fixes parallelism in the OpenSSL build.  For [complicated reasons][1], a sub-Make will not inherit `-j` options from its parent process unless it is invoked directly from another Makefile.  This means we should run make from openssl.makefile rather than openssl.sh.

r? @larsbergstrom

[1]: http://make.mad-scientist.net/papers/jobserver-implementation/

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python/servo/post_build_commands.py

@@ -194,10 +194,7 @@ class PostBuildCommands(CommandBase):
                      help='Package the release build')
     @CommandArgument('--dev', '-d', action='store_true',
                      help='Package the dev build')
-    @CommandArgument(
-        'params', nargs='...',
-        help="Command-line arguments to be passed through to Servo")
-    def package(self, params, release=False, dev=False, debug=False, debugger=None):
+    def package(self, release=False, dev=False, debug=False, debugger=None):
         env = self.build_env()
         binary_path = self.get_binary_path(release, dev, android=True)
 
@@ -218,3 +215,26 @@ class PostBuildCommands(CommandBase):
         except subprocess.CalledProcessError as e:
             print("Packaging Android exited with return value %d" % e.returncode)
             return e.returncode
+
+    @Command('install',
+             description='Install Servo (currently, Android only)',
+             category='post-build')
+    @CommandArgument('--release', '-r', action='store_true',
+                     help='Package the release build')
+    @CommandArgument('--dev', '-d', action='store_true',
+                     help='Package the dev build')
+    def install(self, release=False, dev=False):
+        binary_path = self.get_binary_path(release, dev, android=True)
+        if not path.exists(binary_path):
+            # TODO: Run the build command automatically?
+            print("Servo build not found. Please run `./mach build` to compile Servo.")
+            return 1
+
+        apk_path = binary_path + ".apk"
+        if not path.exists(apk_path):
+            result = Registrar.dispatch("package", context=self.context, release=release, dev=dev)
+            if result is not 0:
+                return result
+
+        print(["adb", "install", "-r", apk_path])
+        return subprocess.call(["adb", "install", "-r", apk_path], env=self.build_env())