remove call to glEnable(GL_TEXTURE_2D) for linux platform

this causes gl errors on linux

Author: Mike Blumenkrantz

src/rendergl.rs

@@ -344,7 +344,9 @@ impl RenderContext {
     pub fn new(compositing_context: NativeCompositingGraphicsContext,
                show_debug_borders: bool) -> RenderContext {
         unsafe { assert_eq!(gl::GetError(), gl::NO_ERROR); }
-        gl::enable(gl::TEXTURE_2D);
+        if cfg!(not(target_os="linux")) {
+            gl::enable(gl::TEXTURE_2D);
+        }
         unsafe { assert_eq!(gl::GetError(), gl::NO_ERROR); }
 
         // Each layer uses premultiplied alpha!