Update build instructions for Linux and Windows.

docs/linux_faster_builds.md

 # Tips for improving build speed on Linux
 
 This list is sorted such that the largest speedup is first; see
 [Linux build instructions](linux_build_instructions.md) for context and
 [Faster Builds](common_build_tasks.md) for non-Linux-specific techniques.
 
 [TOC]
 
+## General configuration
+
+The [GN build configuration](https://www.chromium.org/developers/gn-build-configuration)
+page discusses a number of options that will speed up your build. In particular:
+
+    is_component_build = true
+    enable_nacl = false
+    symbol_level = 0
+    remove_webcore_debug_symbols = true
+
 ## Use goma
 
 If you work at Google, you can use goma for distributed builds; this is similar
 to [distcc](http://en.wikipedia.org/wiki/Distcc). See [go/ma](http://go/ma) for
 documentation.
 
 Even without goma, you can do distributed builds with distcc (if you have access
 to other machines), or a parallel build locally if have multiple cores.
 
 Whether using goma, distcc, or parallel building, you can specify the number of
 build processes with `-jX` where `X` is the number of processes to start.
 
 ## Use Icecc
 
 [Icecc](https://github.com/icecc/icecream) is the distributed compiler with a
 central scheduler to share build load. Currently, many external contributors use
 it. e.g. Intel, Opera, Samsung.
 
-When you use Icecc, you need to set some gyp variables.
+When you use Icecc, you need to [set some GN variables](https://www.chromium.org/developers/gn-build-configuration).
 
-    linux_use_bundled_binutils=0**
+    linux_use_bundled_binutils = false
 
-`-B` option is not supported.
+The `-B` option is not supported.
 [relevant commit](https://github.com/icecc/icecream/commit/b2ce5b9cc4bd1900f55c3684214e409fa81e7a92)
 
-    linux_use_debug_fission=0
+    linux_use_debug_fission = false
 
 [debug fission](http://gcc.gnu.org/wiki/DebugFission) is not supported.
 [bug](https://github.com/icecc/icecream/issues/86)
 
-    clang=0
+    is_clang = false
 
 Icecc doesn't support clang yet.
 
-    use_sysroot=0
+    use_sysroot = false
 
 Icecc doesn't work with sysroot.
 
-    linux_use_bundled_gold=0
-
 Using the system linker is necessary when using glibc 2.21 or newer. See
 [related bug](https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=808181).
-
-## Build only specific targets
-
-If you specify just the target(s) you want built, the build will only walk that
-portion of the dependency graph:
-
-    cd $CHROMIUM_ROOT/src
-    ninja -C out/Debug base_unittests
-
-## Linking
-
-### Dynamically link
-
-We normally statically link everything into one final executable, which produces
-enormous (nearly 1gb in debug mode) files. If you dynamically link, you save a
-lot of time linking for a bit of time during startup, which is fine especially
-when you're in an edit/compile/test cycle.
-
-Add the flag `is_component_build=true` in your build args (to edit build args
-run `gn args out/foo` where `out/foo` is your build directory).
-
-See the
-[component build page](http://www.chromium.org/developers/how-tos/component-build)
-for more information.
-
-### Linking using gold
-
-The experimental "gold" linker is much faster than the standard BFD linker.
-
-On some systems (including Debian experimental, Ubuntu Karmic and beyond), there
-exists a `binutils-gold` package. Do not install this version! Having gold as
-the default linker is known to break kernel / kernel module builds.
-
-The Chrome tree now includes a binary of gold compiled for x64 Linux. It is used
-by default on those systems.
-
-On other systems, to safely install gold, make sure the final binary is named
-`ld` and then set `CC/CXX` appropriately, e.g.
-`export CC="gcc -B/usr/local/gold/bin"` and similarly for `CXX`. Alternatively,
-you can add `/usr/local/gold/bin` to your `PATH` in front of `/usr/bin`.
+Previously these instructions listed the linux_use_bundled_gold GYP variable
+which no longer exists. If you know about this, please update or delete this
+section.
 
 ## WebKit
 
 ### Build WebKit without debug symbols
 
 WebKit is about half our weight in terms of debug symbols. (Lots of templates!)
 If you're working on UI bits where you don't care to trace into WebKit you can
 cut down the size and slowness of debug builds significantly by building WebKit
 without debug symbols.
 
@@ skipping 44 matching lines @@
 or for a release build.
 ***
 
 Quick and dirty benchmark numbers on a HP Z600 (Intel core i7, 16 cores
 hyperthreaded, 12 GB RAM)
 
 *   With tmpfs:
     *   12m:20s
 *   Without tmpfs
     *   15m:40s