Starting work on full GN build

build/config/sysroot.gni

Index: build/config/sysroot.gni
diff --git a/build/config/sysroot.gni b/build/config/sysroot.gni
index 5bce02e29856dff7f1fd979d9a45d98cbae11f83..37faae059c3ee5af5cf67180cda341f8840162b5 100644
--- a/build/config/sysroot.gni
+++ b/build/config/sysroot.gni
@@ -5,8 +5,6 @@
 # This header file defines the "sysroot" variable which is the absolute path
 # of the sysroot. If no sysroot applies, the variable will be an empty string.
 
-import("//build/config/chrome_build.gni")
-
 declare_args() {
   # The absolute path of the sysroot that is applied when compiling using
   # the target toolchain.
@@ -32,29 +30,9 @@ if (current_toolchain == default_toolchain && target_sysroot != "") {
   } else {
     sysroot = ""
   }
-} else if (is_linux && is_chrome_branded && is_official_build && !is_chromeos) {
-  # For official builds, use the sysroot checked into the internal source repo
-  # so that the builds work on older versions of Linux.
-  if (current_cpu == "x64") {
-    sysroot = rebase_path("//build/linux/debian_wheezy_amd64-sysroot")
-  } else if (current_cpu == "x86") {
-    sysroot = rebase_path("//build/linux/debian_wheezy_i386-sysroot")
-  } else {
-    # Any other builds don't use a sysroot.
-    sysroot = ""
-  }
-} else if (is_linux && !is_chromeos) {
-  if (current_cpu == "mipsel") {
-    sysroot = rebase_path("//mipsel-sysroot/sysroot")
-  } else {
-    sysroot = ""
-  }
 } else if (is_mac) {
   import("//build/config/mac/mac_sdk.gni")
   sysroot = mac_sdk_path
-} else if (is_ios) {
-  import("//build/config/ios/ios_sdk.gni")
-  sysroot = ios_sdk_path
 } else {
   sysroot = ""
 }