Auto merge of rust-windowing#130 - sotaroikeda:gl, r=jdm

Update gl_generator to 0.6

Fixes rust-windowing#129

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "servo-glutin"
-version = "0.12.1"
+version = "0.12.2"
 authors = ["The glutin contributors, Pierre Krieger <pierre.krieger1708@gmail.com>"]
 description = "Cross-platform OpenGL context provider."
 keywords = ["windowing", "opengl"]
@@ -23,7 +23,7 @@ libc = "0.2"
 shared_library = "0.1.0"
 
 [build-dependencies]
-gl_generator = "0.5"
+gl_generator = "0.6"
 
 [target.'cfg(target_os = "android")'.dependencies.android_glue]
 version = "0.2"