Auto merge of #20307 - csmoe:measure_query_time, r=jdm

Measure time required before a layout query is serviced by the layout thread

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- [X] extract QueryMsg from ReflowGoal
- [X] introduce QueryMsg timestamp

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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 #19795 (github issue number if applicable).

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components/script_layout_interface/Cargo.toml

@@ -20,6 +20,7 @@ html5ever = "0.22"
 ipc-channel = "0.10"
 libc = "0.2"
 log = "0.3.5"
+time = "0.1.17"
 malloc_size_of = { path = "../malloc_size_of" }
 malloc_size_of_derive = { path = "../malloc_size_of_derive" }
 metrics = {path = "../metrics"}