message: Remove references to json
diff: @@ -596,7 +596,7 @@ pub fn create_bcx<'a, 'cfg>(
  }
  if let Some(filter) = rustdoc_scrape_examples {
  - // Run cargo rustdoc --scrape-examples to generate calls.jsons for each file in `filter`
  + // Run cargo rustdoc --scrape-examples to generate calls for each file in `filter`
  let paths = {
  // Run in doc mode with the given `filter`
  let compile_mode = CompileMode::Doc { deps: false };
  @@ -612,7 +612,7 @@ pub fn create_bcx<'a, 'cfg>(
  let interner = UnitInterner::new();
  let mut bcx = create_bcx(ws, &example_compile_opts, &interner)?;
  - // Make an output path for calls.json for each build unit
  + // Make an output path for calls for each build unit
  let paths = {
  // FIXME(wcrichto): is there a better place to store these files?
  let dest = bcx.profiles.get_dir_name();
  @@ -620,7 +620,7 @@ pub fn create_bcx<'a, 'cfg>(
  let output_dir = layout.prepare_tmp()?;
  bcx.roots
  .iter()
  - .map(|unit| output_dir.join(format!("{}-calls.json", unit.buildkey())))
  + .map(|unit| output_dir.join(format!("{}.calls", unit.buildkey())))
  .collect::<Vec<_>>()
  };
  @@ -688,7 +688,7 @@ pub fn create_bcx<'a, 'cfg>(
  paths
  };
  - // Add "--with-examples *-calls.json" to the current rustdoc invocation
  + // Add "--with-examples *.calls" to the current rustdoc invocation
  let args = paths
  .into_iter()
  .map(|path| vec!["--with-examples".into(), path.into_os_string()].into_iter())
  