Emit trace-enter op before function parameter trace-var ops.

In order to associate the parameters with the inner function, the
trace-var op needs to happen inside the trace-enter. To make this
happen, the parameter handling logic has been moved from
`writeFunction` to `pushFunctionCall`.

Change-Id: Iafd57d0f1de8d23b5a0a98ff2518c00d07532e77
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/664336
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
5 files changed