compiler: change Expression export to use Export_function_body
In preparation for writing expressions to inline function bodies,
change the existing expression export code to use Export_function_body
rather than Export. Adjust existing expression exporters accordingly.
This is a refactoring that doesn't affect compiler output.
Change-Id: I998dae2b3bdf039b7bea636b1118b1bc2d5106fd
Reviewed-on: https://go-review.googlesource.com/c/150063
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
6 files changed
