Auto merge of #7547 - connorimes:move_script_profiling, r=jdm

Combine script profiling with profile crates. Fixes #7514.

The script crate had its own built-in profiling which was basically doing the same thing as the profile crate.  This wraps the internal profiling around the main profile functionality.  Script-related tasks are now added to the ProfilerCategory enum.

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components/compositing/pipeline.rs

@@ -331,6 +331,7 @@ impl PipelineContent {
                                   self.resource_task,
                                   self.storage_task.clone(),
                                   self.image_cache_task.clone(),
+                                  self.time_profiler_chan.clone(),
                                   self.mem_profiler_chan.clone(),
                                   self.devtools_chan,
                                   self.window_size,