Expand variables in inclues sections.
Expand variables in inclues sections.

Patch by Yaar Schnitman <yaar@chromium.org>

Review URL: http://codereview.chromium.org/193130


git-svn-id: e7e1075985beda50ea81ac4472467b4f6e91fc78@658 78cadc50-ecff-11dd-a971-7dbc132099af

lianliuwei/gyp,mkrautz/gyp-libmumble,alexcrichton/gyp,turbulenz/gyp,svn2github/gyp,ttyangf/pdfium_gyp,ttyangf/gyp,sanyaade-teachings/gyp,azunite/gyp,chromium/gyp,yangrongwei/gyp,trafi/gyp,ttyangf/gyp,azunite/gyp,chromium/gyp,enkripsi/gyp,ttyangf/pdfium_gyp,openpeer/webrtc-gyp,svn2github/kgyp,dougbeal/gyp,clar/gyp,cysp/gyp,amoikevin/gyp,openpeer/webrtc-gyp,clar/gyp,yinquan529/platform-external-chromium_org-tools-gyp,pandaxcl/gyp,brson/gyp,sport-monkey/GYP,Chilledheart/gyp,mgamer/gyp,svn2github/gyp,mkrautz/gyp-libmumble,bnoordhuis/gyp,trafi/gyp,saghul/gyn,cysp/gyp,sanyaade-teachings/gyp,MIPS/external-chromium_org-tools-gyp,ryfx/gyp,azunite/gyp_20150930,ryfx/gyp,springmeyer/gyp,svn2github/gyp,channing/gyp,trafi/gyp,AWhetter/gyp,carlTLR/gyp,pyokagan/gyp,okumura/gyp,mumble-voip/libmumble-gyp,AWhetter/gyp,tarc/gyp,okwasi/gyp,clar/gyp,Jack-Q/GYP-copy,ttyangf/pdfium_gyp,mapbox/gyp,MIPS/external-chromium_org-tools-gyp,Omegaphora/external_chromium_org_tools_gyp,amoikevin/gyp,MIPS/external-chromium_org-tools-gyp,bdarnell/gyp,amoikevin/gyp,yangrongwei/gyp,mumble-voip/libmumble-gyp,trafi/gyp,sloanyang/gyp,bnoordhuis/gyp,enkripsi/gyp,okwasi/gyp,pyokagan/gyp,springmeyer/gyp,android-ia/platform_external_chromium_org_tools_gyp,sloanyang/gyp,bpsinc-native/src_tools_gyp,duanhjlt/gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,ttyangf/gyp,kevinchen3315/gyp-git,sfiera/gyp,lukeweber/gyp-override,pandaxcl/gyp,IllusionRom-deprecated/android_platform_external_chromium_org_tools_gyp,carlTLR/gyp,yjhjstz/gyp,Phuehvk/gyp,ttyangf/pdfium_gyp,Jack-Q/GYP-copy,mgamer/gyp,sdklite/gyp,ttyangf/gyp,lianliuwei/gyp,msc-/gyp,LazyCodingCat/gyp,adblockplus/gyp,bdarnell/gyp,bulldy80/gyp_unofficial,adblockplus/gyp,msc-/gyp,bnq4ever/gypgoogle,Omegaphora/external_chromium_org_tools_gyp,okumura/gyp,omasanori/gyp,luvit/gyp,pandaxcl/gyp,azunite/gyp,enkripsi/gyp,cchamberlain/gyp,springmeyer/gyp,luvit/gyp,yjhjstz/gyp,svn2github/gyp,chromium/gyp,bnq4ever/gypgoogle,xin3liang/platform_external_chromium_org_tools_gyp,lianliuwei/gyp,ttyangf/pdfium_gyp,erikge/watch_gyp,kevinchen3315/gyp-git,saghul/gyn,duanhjlt/gyp,pyokagan/gyp,svn2github/kgyp,Danath/gyp,adblockplus/gyp,Phuehvk/gyp,yangrongwei/gyp,ttyangf/gyp,AOSPU/external_chromium_org_tools_gyp,yjhjstz/gyp,mgamer/gyp,svn2github/kgyp,luvit/gyp,dougbeal/gyp,mapbox/gyp,erikge/watch_gyp,Phuehvk/gyp,clar/gyp,adblockplus/gyp,sdklite/gyp,Danath/gyp,channing/gyp,turbulenz/gyp,springmeyer/gyp,Danath/gyp,IllusionRom-deprecated/android_platform_external_chromium_org_tools_gyp,bpsinc-native/src_tools_gyp,azunite/gyp,bulldy80/gyp_unofficial,mgamer/gyp,alexcrichton/gyp,omasanori/gyp,Jack-Q/GYP-copy,carlTLR/gyp,AWhetter/gyp,LazyCodingCat/gyp,cchamberlain/gyp,azunite/gyp_20150930,AOSPU/external_chromium_org_tools_gyp,erikge/watch_gyp,enkripsi/gyp,kevinchen3315/gyp-git,LazyCodingCat/gyp,amoikevin/gyp,geekboxzone/lollipop_external_chromium_org_tools_gyp,ryfx/gyp,tarc/gyp,bdarnell/gyp,AOSPU/external_chromium_org_tools_gyp,mumble-voip/libmumble-gyp,yjhjstz/gyp,azunite/gyp_20150930,geekboxzone/lollipop_external_chromium_org_tools_gyp,msc-/gyp,duanhjlt/gyp,mgamer/gyp,amoikevin/gyp,mistydemeo/gyp,bpsinc-native/src_tools_gyp,sanyaade-teachings/gyp,saghul/gyn,erikge/watch_gyp,svn2github/gyp,AWhetter/gyp,sloanyang/gyp,tarc/gyp,brson/gyp,sanyaade-teachings/gyp,clar/gyp,cchamberlain/gyp,tarc/gyp,mapbox/gyp,svn2github/kgyp,sport-monkey/GYP,springmeyer/gyp,mistydemeo/gyp,mapbox/gyp,Jack-Q/GYP-copy,bulldy80/gyp_unofficial,cysp/gyp,duanhjlt/gyp,pyokagan/gyp,bnoordhuis/gyp,mapbox/gyp,turbulenz/gyp,turbulenz/gyp,LazyCodingCat/gyp,sport-monkey/GYP,tarc/gyp,sdklite/gyp,saghul/gyn,Chilledheart/gyp,Chilledheart/gyp,duanhjlt/gyp,lukeweber/gyp-override,cysp/gyp,omasanori/gyp,alexcrichton/gyp,xin3liang/platform_external_chromium_org_tools_gyp,dougbeal/gyp,sdklite/gyp,saghul/gyn,bpsinc-native/src_tools_gyp,trafi/gyp,Danath/gyp,ryfx/gyp,mumble-voip/libmumble-gyp,okwasi/gyp,android-ia/platform_external_chromium_org_tools_gyp,xin3liang/platform_external_chromium_org_tools_gyp,cchamberlain/gyp,Chilledheart/gyp,okwasi/gyp,sloanyang/gyp,bnq4ever/gypgoogle,yinquan529/platform-external-chromium_org-tools-gyp,MIPS/external-chromium_org-tools-gyp,Jack-Q/GYP-copy,dougbeal/gyp,chromium/gyp,chromium/gyp,yinquan529/platform-external-chromium_org-tools-gyp,bnoordhuis/gyp,bnq4ever/gypgoogle,cysp/gyp,alexcrichton/gyp,bulldy80/gyp_unofficial,android-ia/platform_external_chromium_org_tools_gyp,brson/gyp,turbulenz/gyp,brson/gyp,cchamberlain/gyp,enkripsi/gyp,openpeer/webrtc-gyp,Phuehvk/gyp,mistydemeo/gyp,channing/gyp,msc-/gyp,bnoordhuis/gyp,mkrautz/gyp-libmumble,sdklite/gyp,bdarnell/gyp,xin3liang/platform_external_chromium_org_tools_gyp,Danath/gyp,pandaxcl/gyp,Phuehvk/gyp,Omegaphora/external_chromium_org_tools_gyp,azunite/gyp,bnq4ever/gypgoogle,channing/gyp,yjhjstz/gyp,omasanori/gyp,okumura/gyp,carlTLR/gyp,lianliuwei/gyp,lukeweber/gyp-override,geekboxzone/lollipop_external_chromium_org_tools_gyp,sfiera/gyp,openpeer/webrtc-gyp,sport-monkey/GYP,Omegaphora/external_chromium_org_tools_gyp,AWhetter/gyp,mkrautz/gyp-libmumble,openpeer/webrtc-gyp,sanyaade-teachings/gyp,yangrongwei/gyp,azunite/gyp_20150930,lukeweber/gyp-override,sfiera/gyp,yinquan529/platform-external-chromium_org-tools-gyp,Chilledheart/gyp,msc-/gyp,AOSPU/external_chromium_org_tools_gyp,sport-monkey/GYP,pyokagan/gyp,okumura/gyp,mistydemeo/gyp,pandaxcl/gyp,adblockplus/gyp,IllusionRom-deprecated/android_platform_external_chromium_org_tools_gyp,IllusionRom-deprecated/android_platform_external_chromium_org_tools_gyp,kevinchen3315/gyp-git,android-ia/platform_external_chromium_org_tools_gyp,erikge/watch_gyp,bulldy80/gyp_unofficial,luvit/gyp,svn2github/kgyp,LazyCodingCat/gyp,carlTLR/gyp,ryfx/gyp,azunite/gyp_20150930,dougbeal/gyp