Auto merge of #23744 - jdm:gles-fixes, r=asajeffrey

Make GL/GLES decisions based on the API in use

These changes remove a number of assumptions about whether GL/GLES is in use, improving the support for running WebGL in Servo under ANGLE.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because no tests on Windows.

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1 files changed, 8 insertions, 2 deletions

diff --git a/components/script/dom/webgl_extensions/extensions.rs b/components/script/dom/webgl_extensions/extensions.rs
index e71fcf7dac5..7beb3081374 100644
--- a/components/script/dom/webgl_extensions/extensions.rs
+++ b/components/script/dom/webgl_extensions/extensions.rs
@@ -18,7 +18,7 @@ use crate::dom::oestexturehalffloat::OESTextureHalfFloat;
 use crate::dom::webglcolorbufferfloat::WEBGLColorBufferFloat;
 use crate::dom::webglrenderingcontext::WebGLRenderingContext;
 use crate::dom::webgltexture::TexCompression;
-use canvas_traits::webgl::WebGLVersion;
+use canvas_traits::webgl::{GlType, WebGLVersion};
 use fnv::{FnvHashMap, FnvHashSet};
 use gleam::gl::{self, GLenum};
 use js::jsapi::JSObject;
@@ -146,14 +146,16 @@ pub struct WebGLExtensions {
     extensions: DomRefCell<HashMap<String, Box<dyn WebGLExtensionWrapper>>>,
     features: DomRefCell<WebGLExtensionFeatures>,
     webgl_version: WebGLVersion,
+    api_type: GlType,
 }
 
 impl WebGLExtensions {
-    pub fn new(webgl_version: WebGLVersion) -> WebGLExtensions {
+    pub fn new(webgl_version: WebGLVersion, api_type: GlType) -> WebGLExtensions {
         Self {
             extensions: DomRefCell::new(HashMap::new()),
             features: DomRefCell::new(WebGLExtensionFeatures::new(webgl_version)),
             webgl_version,
+            api_type,
         }
     }
 
@@ -425,6 +427,10 @@ impl WebGLExtensions {
         }
         type_
     }
+
+    pub fn is_gles(&self) -> bool {
+        self.api_type == GlType::Gles
+    }
 }
 
 // Helper structs