Bug 1368699 - Pre: Remove MY_{CONFIG,RULES} Makefile customization hooks. r=gps

I very much doubt these are used, but even if we are -- we shouldn't
support this type of local customization, since it doesn't extend to
non-Make-based backends.

With the customization point removed, there's no way to set ETAGS, so
we remove what little support there was for generating Emacs tags.

MozReview-Commit-ID: IEF2Q4tISEn

--HG--
extra : rebase_source : 140e07f78dbd72391c70c48f25e2b85c924fe78d

config/config.mk

@@ -179,12 +179,6 @@ endif
 
 TAR_CREATE_FLAGS = -chf
 
-#
-# Personal makefile customizations go in these optional make include files.
-#
-MY_CONFIG	:= $(DEPTH)/config/myconfig.mk
-MY_RULES	:= $(DEPTH)/config/myrules.mk
-
 #
 # Default command macros; can be overridden in <arch>.mk.
 #
@@ -296,11 +290,7 @@ endif
 endif
 endif
 
-#
-# Include any personal overrides the user might think are needed.
-#
 -include $(topsrcdir)/$(MOZ_BUILD_APP)/app-config.mk
--include $(MY_CONFIG)
 
 ######################################################################
 

config/rules.mk

@@ -1344,19 +1344,6 @@ endif
 #############################################################################
 
 -include $(topsrcdir)/$(MOZ_BUILD_APP)/app-rules.mk
--include $(MY_RULES)
-
-#
-# Generate Emacs tags in a file named TAGS if ETAGS was set in $(MY_CONFIG)
-# or in $(MY_RULES)
-#
-ifdef ETAGS
-ifneq ($(CSRCS)$(CPPSRCS)$(HEADERS),)
-all:: TAGS
-TAGS:: $(CSRCS) $(CPPSRCS) $(HEADERS)
-	$(ETAGS) $(CSRCS) $(CPPSRCS) $(HEADERS)
-endif
-endif
 
 ################################################################################
 # Install/copy rules