Bug 1275740 - Use compression level 5 instead of 9 for symbols zips; r=ted

On my i7-6700K time and size for the full zip archive for a Windows
debug build is as follows:

          Time       Size
Before:   25.4s    278,708,278
After:    13.0s    280,623,521

Anything lower than level 5 and the archive size starts increasing by
several megabytes. Level 5 is definitely the sweet spot.

MozReview-Commit-ID: 9lW2W1htq93

--HG--
extra : rebase_source : 26458386e4032dfd85eddd937bf6e6bff057d99b

Makefile.in

@@ -309,12 +309,12 @@ ifdef MOZ_CRASHREPORTER
 	echo packing symbols
 	$(NSINSTALL) -D $(DIST)/$(PKG_PATH)
 	cd $(DIST)/crashreporter-symbols && \
-          zip -r9D '../$(PKG_PATH)$(SYMBOL_FULL_ARCHIVE_BASENAME).zip' . -x '*test*' -x '*Test*'
+          zip -r5D '../$(PKG_PATH)$(SYMBOL_FULL_ARCHIVE_BASENAME).zip' . -x '*test*' -x '*Test*'
 	cd $(DIST)/crashreporter-symbols && \
 	grep 'sym' $(SYMBOL_INDEX_NAME) > $(SYMBOL_INDEX_NAME).tmp && \
 	  mv $(SYMBOL_INDEX_NAME).tmp $(SYMBOL_INDEX_NAME)
 	cd $(DIST)/crashreporter-symbols && \
-          zip -r9D '../$(PKG_PATH)$(SYMBOL_ARCHIVE_BASENAME).zip' . -i '*.sym' -i '*.txt'  -x '*test*' -x '*Test*'
+          zip -r5D '../$(PKG_PATH)$(SYMBOL_ARCHIVE_BASENAME).zip' . -i '*.sym' -i '*.txt'  -x '*test*' -x '*Test*'
 endif # MOZ_CRASHREPORTER
 
 uploadsymbols: