Rename the fallback proc menubarheight to testmenubarheight. In [d5e6…

…02691a], in branch less_tests_constraints created off core-8-6-branch, I have renamed proc menubarheight to testmenubarheight to conform to how other such procs are named in the test suite. Later, in [e78b5c12b6] in trunk, I have added a fallback for that proc to be used by platforms other than macOS. And again later in [49fdd4b212] I have merged trunk in less_tests_constraints. This last commit created the inconsistency.

tests/constraints.tcl

@@ -246,21 +246,21 @@ namespace eval tk {
 	# got moved to the requested location should use a y coordinate larger than the
 	# height of the menubar (normally 23 pixels) and an x coordinate larger than the
 	# width of the dock, if it happens to be on the left.
-	# menubarheight deals with this issue but may not be available from the test
+	# testmenubarheight deals with this issue but may not be available from the test
 	# environment, therefore provide a fallback here
-	if {[llength [info procs menubarheight]] == 0} {
+	if {[llength [info procs testmenubarheight]] == 0} {
 	    if {[tk windowingsystem] ne "aqua"} {
 		# Windows may overlap the menubar
-		proc menubarheight {} {
+		proc testmenubarheight {} {
 		    return 0
 		}
 	    } else {
 		# Windows may not overlap the menubar
-		proc menubarheight {} {
+		proc testmenubarheight {} {
 		    return 30 ;  # arbitrary value known to be larger than the menubar height
 		}
 	    }
-	    namespace export menubarheight
+	    namespace export testmenubarheight
 	}
     }
 }