From 99b6091b7a2d0782e60cef881cd2a48e44df4654 Mon Sep 17 00:00:00 2001
From: Anthony Ramine <n.oxyde@gmail.com>
Date: Tue, 2 Oct 2018 11:20:05 +0200
Subject: [PATCH] Clean up create_webgl_context

---
 components/canvas/webgl_thread.rs | 76 +++++++++++++++----------------
 1 file changed, 37 insertions(+), 39 deletions(-)

diff --git a/components/canvas/webgl_thread.rs b/components/canvas/webgl_thread.rs
index 4d8a4c044a2..74f25b7768b 100644
--- a/components/canvas/webgl_thread.rs
+++ b/components/canvas/webgl_thread.rs
@@ -216,50 +216,48 @@ impl<VR: WebVRRenderHandler + 'static> WebGLThread<VR> {
     }
 
     /// Creates a new WebGLContext
-    fn create_webgl_context(&mut self,
-                            version: WebGLVersion,
-                            size: Size2D<i32>,
-                            attributes: GLContextAttributes)
-                            -> Result<(WebGLContextId, GLLimits, WebGLContextShareMode), String> {
-        // First try to create a shared context for the best performance.
-        // Fallback to readback mode if the shared context creation fails.
-        let result = self.gl_factory.new_shared_context(version, size, attributes)
-                                    .map(|r| (r, WebGLContextShareMode::SharedTexture))
-                                    .or_else(|err| {
-                                        warn!("Couldn't create shared GL context ({}), using slow \
-                                               readback context instead.", err);
-                                        let ctx = self.gl_factory.new_context(version, size, attributes);
-                                        ctx.map(|r| (r, WebGLContextShareMode::Readback))
-                                    });
-
+    fn create_webgl_context(
+        &mut self,
+        version: WebGLVersion,
+        size: Size2D<i32>,
+        attributes: GLContextAttributes,
+    ) -> Result<(WebGLContextId, GLLimits, WebGLContextShareMode), String> {
         // Creating a new GLContext may make the current bound context_id dirty.
         // Clear it to ensure that  make_current() is called in subsequent commands.
         self.bound_context_id = None;
 
-        match result {
-            Ok((ctx, share_mode)) => {
-                let id = WebGLContextId(self.next_webgl_id);
-                let (size, texture_id, limits) = ctx.get_info();
-                self.next_webgl_id += 1;
-                self.contexts.insert(id, GLContextData {
-                    ctx,
-                    state: Default::default(),
-                });
-                self.cached_context_info.insert(id, WebGLContextInfo {
-                    texture_id,
-                    size,
-                    alpha: attributes.alpha,
-                    image_key: None,
-                    share_mode,
-                    gl_sync: None,
-                });
+        // First try to create a shared context for the best performance.
+        // Fallback to readback mode if the shared context creation fails.
+        let (ctx, share_mode) = self.gl_factory
+            .new_shared_context(version, size, attributes)
+            .map(|r| (r, WebGLContextShareMode::SharedTexture))
+            .or_else(|err| {
+                warn!(
+                    "Couldn't create shared GL context ({}), using slow readback context instead.",
+                    err
+                );
+                let ctx = self.gl_factory.new_context(version, size, attributes)?;
+                Ok((ctx, WebGLContextShareMode::Readback))
+            })
+            .map_err(|msg| msg.to_owned())?;
 
-                Ok((id, limits, share_mode))
-            },
-            Err(msg) => {
-                Err(msg.to_owned())
-            }
-        }
+        let id = WebGLContextId(self.next_webgl_id);
+        let (size, texture_id, limits) = ctx.get_info();
+        self.next_webgl_id += 1;
+        self.contexts.insert(id, GLContextData {
+            ctx,
+            state: Default::default(),
+        });
+        self.cached_context_info.insert(id, WebGLContextInfo {
+            texture_id,
+            size,
+            alpha: attributes.alpha,
+            image_key: None,
+            share_mode,
+            gl_sync: None,
+        });
+
+        Ok((id, limits, share_mode))
     }
 
     /// Resizes a WebGLContext