runtime: remove minSched hack for wasm

I am not entirely sure what it's doing (it seems related to js.FuncOf),
but tests still seem to pass when this code is removed. So let's remove
it.

src/runtime/runtime_wasm_js_scheduler.go

@@ -8,24 +8,10 @@ func resume() {
 		handleEvent()
 	}()
 
-	if wasmNested {
-		minSched()
-		return
-	}
-
-	wasmNested = true
 	scheduler(false)
-	wasmNested = false
 }
 
 //export go_scheduler
 func go_scheduler() {
-	if wasmNested {
-		minSched()
-		return
-	}
-
-	wasmNested = true
 	scheduler(false)
-	wasmNested = false
 }