all: windows build tags

For golang/go#9306

Change-Id: Ia8778f5b371371d103c55c12606257ee7ca45fd4
Reviewed-on: https://go-review.googlesource.com/17778
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
diff --git a/asset/asset.go b/asset/asset.go
index 90a2bb2..e81b7f3 100644
--- a/asset/asset.go
+++ b/asset/asset.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 package asset
 
diff --git a/asset/asset_desktop.go b/asset/asset_desktop.go
index b23a6a3..21a1d71 100644
--- a/asset/asset_desktop.go
+++ b/asset/asset_desktop.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build linux,!android darwin,!arm,!arm64
+// +build linux,!android darwin,!arm,!arm64 windows
 
 package asset
 
diff --git a/example/basic/main.go b/example/basic/main.go
index 2b2e0c9..b25f81e 100644
--- a/example/basic/main.go
+++ b/example/basic/main.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 // An app that draws a green triangle on a red background.
 //
diff --git a/example/basic/main_x.go b/example/basic/main_x.go
index 3d440e7..6b8c13f 100644
--- a/example/basic/main_x.go
+++ b/example/basic/main_x.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !darwin,!linux
+// +build !darwin,!linux,!windows
 
 package main
 
diff --git a/example/network/main.go b/example/network/main.go
index 8fba730..c1d26dc 100644
--- a/example/network/main.go
+++ b/example/network/main.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 // An app that paints green if golang.org is reachable when the app first
 // starts, or red otherwise.
diff --git a/example/network/main_x.go b/example/network/main_x.go
index e528533..2558269 100644
--- a/example/network/main_x.go
+++ b/example/network/main_x.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !darwin,!linux
+// +build !darwin,!linux,!windows
 
 package main
 
diff --git a/example/sprite/main.go b/example/sprite/main.go
index 1436ab9..e85c3c0 100644
--- a/example/sprite/main.go
+++ b/example/sprite/main.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 // An app that demonstrates the sprite package.
 //
diff --git a/example/sprite/main_x.go b/example/sprite/main_x.go
index 3d440e7..6b8c13f 100644
--- a/example/sprite/main_x.go
+++ b/example/sprite/main_x.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !darwin,!linux
+// +build !darwin,!linux,!windows
 
 package main
 
diff --git a/exp/app/debug/fps.go b/exp/app/debug/fps.go
index 16eab6e..ef64966 100644
--- a/exp/app/debug/fps.go
+++ b/exp/app/debug/fps.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 // Package debug provides GL-based debugging tools for apps.
 package debug // import "golang.org/x/mobile/exp/app/debug"
diff --git a/exp/gl/glutil/glimage.go b/exp/gl/glutil/glimage.go
index 497fd89..55aba42 100644
--- a/exp/gl/glutil/glimage.go
+++ b/exp/gl/glutil/glimage.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build linux darwin
+// +build linux darwin windows
 
 package glutil
 
diff --git a/exp/gl/glutil/glutil.go b/exp/gl/glutil/glutil.go
index d742913..5acafb5 100644
--- a/exp/gl/glutil/glutil.go
+++ b/exp/gl/glutil/glutil.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 package glutil // import "golang.org/x/mobile/exp/gl/glutil"
 
diff --git a/exp/sprite/glsprite/glsprite.go b/exp/sprite/glsprite/glsprite.go
index f5b6a77..3282dae 100644
--- a/exp/sprite/glsprite/glsprite.go
+++ b/exp/sprite/glsprite/glsprite.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin linux
+// +build darwin linux windows
 
 // Package glsprite implements a sprite Engine using OpenGL ES 2.
 //