Auto merge of #20396 - Xanewok:webgl-typed-arrays, r=jdm

Replace `object` function arguments in WebGL with typed arrays

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Could use a https://github.com/servo/rust-mozjs/pull/402 in some places, as this should simplify a little bit and remove unnecessary `#[allow(unsafe_code)]` attributes.

I sort of hacked my way through for https://github.com/servo/servo/issues/20394 since I encountered this issue as well. I agree that the comment above makes me feel uneasy about this and feels like I'm missing something and this shouldn't be the way we eventually resolve the overloads with auto rootable types (talking about this: https://github.com/servo/servo/pull/20396/files#diff-60d01595cff328c165842fea9e4ccbc2R428).

r? @jdm

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20342 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because if the bindings compile now, it works!

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1 files changed, 8 insertions, 7 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 24054de8e95..de991f35ed9 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -422,7 +422,8 @@ class CGMethodCall(CGThing):
                         template,
                         {"val": distinguishingArg},
                         declType,
-                        "arg%d" % distinguishingIndex)
+                        "arg%d" % distinguishingIndex,
+                        needsAutoRoot=type_needs_auto_root(type))
 
                     # Indent by 4, since we need to indent further than our "do" statement
                     caseBody.append(CGIndenter(testCode, 4))
@@ -1211,7 +1212,8 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
 
 
 def instantiateJSToNativeConversionTemplate(templateBody, replacements,
-                                            declType, declName):
+                                            declType, declName,
+                                            needsAutoRoot=False):
     """
     Take the templateBody and declType as returned by
     getJSToNativeConversionInfo, a set of replacements as required by the
@@ -1236,6 +1238,8 @@ def instantiateJSToNativeConversionTemplate(templateBody, replacements,
     else:
         result.append(conversion)
 
+    if needsAutoRoot:
+        result.append(CGGeneric("auto_root!(in(cx) let %s = %s);" % (declName, declName)))
     # Add an empty CGGeneric to get an extra newline after the argument
     # conversion.
     result.append(CGGeneric(""))
@@ -1318,11 +1322,8 @@ class CGArgumentConverter(CGThing):
             arg = "arg%d" % index
 
             self.converter = instantiateJSToNativeConversionTemplate(
-                template, replacementVariables, declType, arg)
-
-            # The auto rooting is done only after the conversion is performed
-            if type_needs_auto_root(argument.type):
-                self.converter.append(CGGeneric("auto_root!(in(cx) let %s = %s);" % (arg, arg)))
+                template, replacementVariables, declType, arg,
+                needsAutoRoot=type_needs_auto_root(argument.type))
 
         else:
             assert argument.optional