Remove third_party/golang.org/x/mobile as it is no longer used with Go 1.5.

third_party/go/src/golang.org/x/mobile/cmd/gomobile/install.go

Index: third_party/go/src/golang.org/x/mobile/cmd/gomobile/install.go
diff --git a/third_party/go/src/golang.org/x/mobile/cmd/gomobile/install.go b/third_party/go/src/golang.org/x/mobile/cmd/gomobile/install.go
deleted file mode 100644
index 615a07a77e3e2caea98816bddecb6ed80678a5f7..0000000000000000000000000000000000000000
--- a/third_party/go/src/golang.org/x/mobile/cmd/gomobile/install.go
+++ /dev/null
@@ -1,43 +0,0 @@
-// Copyright 2015 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
-	"os"
-	"os/exec"
-	"path/filepath"
-)
-
-var cmdInstall = &command{
-	run:   runInstall,
-	Name:  "install",
-	Usage: "[package]",
-	Short: "compile android APK and/or iOS app and install on device",
-	Long: `
-Install compiles and installs the app named by the import path on the
-attached mobile device.
-
-This command requires the 'adb' tool on the PATH.
-
-See the build command help for common flags and common behavior.
-`,
-}
-
-func runInstall(cmd *command) error {
-	if err := runBuild(cmd); err != nil {
-		return err
-	}
-	install := exec.Command(
-		`adb`,
-		`install`,
-		`-r`,
-		filepath.Base(pkg.Dir)+`.apk`,
-	)
-	if buildV {
-		install.Stdout = os.Stdout
-		install.Stderr = os.Stderr
-	}
-	return install.Run()
-}