Make tracing trait opt-out via env only

Author: kateinoigakukun

Makefile

@@ -1,4 +1,5 @@
 SWIFT_SDK_ID ?=
+DISABLE_TRACING ?= $(JAVASCRIPTKIT_DISABLE_TRACING_TRAIT)
 
 .PHONY: bootstrap
 bootstrap:
@@ -11,7 +12,7 @@ unittest:
 		echo "SWIFT_SDK_ID is not set. Run 'swift sdk list' and pass a matching SDK, e.g. 'make unittest SWIFT_SDK_ID=<id>'."; \
 		exit 2; \
 	}
-ifeq ($(JAVASCRIPTKIT_DISABLE_TRACING_TRAIT),1)
+ifeq ($(DISABLE_TRACING),1)
 	TRACING_ARGS :=
 else
 	TRACING_ARGS := --traits Tracing

Sources/JavaScriptKit/FundamentalObjects/JSClosure.swift

@@ -338,18 +338,18 @@ func _call_host_function_impl(
     guard let entry = JSClosure.sharedClosures.wrappedValue[hostFuncRef] else {
         return true
     }
-#if Tracing
+    #if Tracing
     let traceEnd = JSTracingHooks.beginJSClosureCall(
         JSTracing.JSClosureCallInfo(fileID: entry.fileID, line: UInt(entry.line))
     )
-#endif
+    #endif
     var arguments: [JSValue] = []
     for i in 0..<Int(argc) {
         arguments.append(argv[i].jsValue)
     }
-#if Tracing
+    #if Tracing
     defer { traceEnd?() }
-#endif
+    #endif
     let result = entry.body(arguments)
     let callbackFuncRef = JSObject(id: callbackFuncRef)
     _ = callbackFuncRef(result)