Honor LDFLAGS on Mac and Win. 
Honor LDFLAGS on Mac and Win. 

BUG=309412
Review URL: https://codereview.chromium.org/30813002/

Patch from James Kozianski <koz@chromium.org>!



git-svn-id: e7e1075985beda50ea81ac4472467b4f6e91fc78@1765 78cadc50-ecff-11dd-a971-7dbc132099af

clar/gyp,springmeyer/gyp,azunite/gyp,android-ia/platform_external_chromium_org_tools_gyp,azunite/gyp,chromium/gyp,mapbox/gyp,mapbox/gyp,luvit/gyp,Omegaphora/external_chromium_org_tools_gyp,ttyangf/gyp,bnoordhuis/gyp,msc-/gyp,cchamberlain/gyp,xin3liang/platform_external_chromium_org_tools_gyp,enkripsi/gyp,yinquan529/platform-external-chromium_org-tools-gyp,omasanori/gyp,Jack-Q/GYP-copy,svn2github/gyp,tarc/gyp,LazyCodingCat/gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,saghul/gyn,clar/gyp,azunite/gyp,bulldy80/gyp_unofficial,sdklite/gyp,ttyangf/pdfium_gyp,Jack-Q/GYP-copy,bulldy80/gyp_unofficial,cysp/gyp,duanhjlt/gyp,bulldy80/gyp_unofficial,trafi/gyp,AWhetter/gyp,mapbox/gyp,svn2github/kgyp,erikge/watch_gyp,AOSPU/external_chromium_org_tools_gyp,trafi/gyp,tarc/gyp,chromium/gyp,duanhjlt/gyp,sdklite/gyp,azunite/gyp_20150930,tarc/gyp,sloanyang/gyp,alexcrichton/gyp,saghul/gyn,Phuehvk/gyp,mgamer/gyp,springmeyer/gyp,mistydemeo/gyp,cchamberlain/gyp,ryfx/gyp,trafi/gyp,mgamer/gyp,turbulenz/gyp,pandaxcl/gyp,alexcrichton/gyp,Danath/gyp,adblockplus/gyp,mgamer/gyp,yjhjstz/gyp,azunite/gyp_20150930,sdklite/gyp,pandaxcl/gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,erikge/watch_gyp,adblockplus/gyp,yinquan529/platform-external-chromium_org-tools-gyp,cysp/gyp,cysp/gyp,yjhjstz/gyp,amoikevin/gyp,erikge/watch_gyp,carlTLR/gyp,trafi/gyp,enkripsi/gyp,Phuehvk/gyp,sdklite/gyp,trafi/gyp,svn2github/gyp,bnq4ever/gypgoogle,sport-monkey/GYP,svn2github/gyp,pyokagan/gyp,AOSPU/external_chromium_org_tools_gyp,pandaxcl/gyp,okumura/gyp,carlTLR/gyp,omasanori/gyp,pyokagan/gyp,sport-monkey/GYP,Danath/gyp,amoikevin/gyp,adblockplus/gyp,yjhjstz/gyp,pandaxcl/gyp,ryfx/gyp,xin3liang/platform_external_chromium_org_tools_gyp,AOSPU/external_chromium_org_tools_gyp,bpsinc-native/src_tools_gyp,carlTLR/gyp,android-ia/platform_external_chromium_org_tools_gyp,turbulenz/gyp,Danath/gyp,Omegaphora/external_chromium_org_tools_gyp,duanhjlt/gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,pyokagan/gyp,ttyangf/pdfium_gyp,amoikevin/gyp,Jack-Q/GYP-copy,cchamberlain/gyp,dougbeal/gyp,Omegaphora/external_chromium_org_tools_gyp,springmeyer/gyp,chromium/gyp,omasanori/gyp,openpeer/webrtc-gyp,cysp/gyp,bpsinc-native/src_tools_gyp,dougbeal/gyp,xin3liang/platform_external_chromium_org_tools_gyp,enkripsi/gyp,alexcrichton/gyp,openpeer/webrtc-gyp,mistydemeo/gyp,xin3liang/platform_external_chromium_org_tools_gyp,erikge/watch_gyp,mgamer/gyp,sanyaade-teachings/gyp,msc-/gyp,bulldy80/gyp_unofficial,ttyangf/pdfium_gyp,tarc/gyp,sanyaade-teachings/gyp,AWhetter/gyp,android-ia/platform_external_chromium_org_tools_gyp,alexcrichton/gyp,svn2github/gyp,openpeer/webrtc-gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,LazyCodingCat/gyp,chromium/gyp,pyokagan/gyp,sanyaade-teachings/gyp,svn2github/kgyp,luvit/gyp,AWhetter/gyp,okumura/gyp,svn2github/kgyp,ttyangf/pdfium_gyp,clar/gyp,sport-monkey/GYP,Jack-Q/GYP-copy,sanyaade-teachings/gyp,springmeyer/gyp,sport-monkey/GYP,carlTLR/gyp,bnoordhuis/gyp,ttyangf/pdfium_gyp,bnq4ever/gypgoogle,yinquan529/platform-external-chromium_org-tools-gyp,tarc/gyp,ttyangf/gyp,luvit/gyp,msc-/gyp,AWhetter/gyp,openpeer/webrtc-gyp,dougbeal/gyp,Chilledheart/gyp,Phuehvk/gyp,sanyaade-teachings/gyp,okumura/gyp,Jack-Q/GYP-copy,Chilledheart/gyp,turbulenz/gyp,amoikevin/gyp,svn2github/kgyp,azunite/gyp_20150930,Chilledheart/gyp,svn2github/kgyp,adblockplus/gyp,bnq4ever/gypgoogle,ttyangf/gyp,clar/gyp,ttyangf/gyp,bnq4ever/gypgoogle,sloanyang/gyp,bnq4ever/gypgoogle,msc-/gyp,bpsinc-native/src_tools_gyp,LazyCodingCat/gyp,luvit/gyp,pyokagan/gyp,msc-/gyp,sdklite/gyp,amoikevin/gyp,bulldy80/gyp_unofficial,azunite/gyp,enkripsi/gyp,ttyangf/gyp,sport-monkey/GYP,Phuehvk/gyp,omasanori/gyp,dougbeal/gyp,openpeer/webrtc-gyp,saghul/gyn,mapbox/gyp,LazyCodingCat/gyp,ryfx/gyp,azunite/gyp_20150930,Danath/gyp,yjhjstz/gyp,azunite/gyp,turbulenz/gyp,svn2github/gyp,carlTLR/gyp,Chilledheart/gyp,ryfx/gyp,pandaxcl/gyp,bpsinc-native/src_tools_gyp,sloanyang/gyp,azunite/gyp_20150930,Chilledheart/gyp,Danath/gyp,yjhjstz/gyp,duanhjlt/gyp,cysp/gyp,mapbox/gyp,Omegaphora/external_chromium_org_tools_gyp,saghul/gyn,erikge/watch_gyp,turbulenz/gyp,cchamberlain/gyp,mistydemeo/gyp,mistydemeo/gyp,LazyCodingCat/gyp,duanhjlt/gyp,bnoordhuis/gyp,cchamberlain/gyp,Phuehvk/gyp,chromium/gyp,clar/gyp,enkripsi/gyp,AOSPU/external_chromium_org_tools_gyp,sloanyang/gyp,dougbeal/gyp,ryfx/gyp,springmeyer/gyp,okumura/gyp,yinquan529/platform-external-chromium_org-tools-gyp,adblockplus/gyp,bnoordhuis/gyp,android-ia/platform_external_chromium_org_tools_gyp,bnoordhuis/gyp,mgamer/gyp,saghul/gyn,AWhetter/gyp