Auto merge of #22214 - jabedude:validate-argument, r=jdm

Add GetShaderPrecisionFormat argument validation

This patch adds a check on the shader_type argument. If it is not one either
FRAGMENT_SHADER or VERTEX_SHADER, we return INVALID_ENUM.

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- [X] These changes fix  #22080
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1 files changed, 8 insertions, 0 deletions

diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index a21d3898112..88948343bdd 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -2549,6 +2549,14 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         shader_type: u32,
         precision_type: u32,
     ) -> Option<DomRoot<WebGLShaderPrecisionFormat>> {
+        match shader_type {
+            constants::FRAGMENT_SHADER | constants::VERTEX_SHADER => (),
+            _ => {
+                self.webgl_error(InvalidEnum);
+                return None;
+            },
+        }
+
         match precision_type {
             constants::LOW_FLOAT |
             constants::MEDIUM_FLOAT |