Add the mini_installer_syzygy GN target.

build/config/compiler/compiler.gni

Index: build/config/compiler/compiler.gni
diff --git a/build/config/compiler/compiler.gni b/build/config/compiler/compiler.gni
index ca677f7a3837ad2a7fc8e85d3a6133a01f026ae2..dd89503e4fcd5e00cb9038d3b5c1788a5578daf5 100644
--- a/build/config/compiler/compiler.gni
+++ b/build/config/compiler/compiler.gni
@@ -21,6 +21,23 @@ declare_args() {
   # example, don't omit the frame pointer and leave in symbols.
   enable_profiling = false
 
+  # use_debug_fission: whether to use split DWARF debug info
+  # files. This can reduce link time significantly, but is incompatible
+  # with some utilities such as icecc and ccache. Requires gold and
+  # gcc >= 4.8 or clang.
+  # http://gcc.gnu.org/wiki/DebugFission
+  #
+  # This is a placeholder value indicating that the code below should set
+  # the default.  This is necessary to delay the evaluation of the default
+  # value expression until after its input values such as use_gold have
+  # been set, e.g. by a toolchain_args() block.
+  use_debug_fission = "default"
+
+  # Tell VS to create a PDB that references information in .obj files rather
+  # than copying it all. This should improve linker performance. mspdbcmf.exe
+  # can be used to convert a fastlink pdb to a normal one.
+  is_win_fastlink = false
+
   # Specify the current PGO phase, only used for the Windows MSVS build. Here's
   # the different values that can be used:
   #     0 : Means that PGO is turned off.
@@ -29,7 +46,9 @@ declare_args() {
   #
   # TODO(sebmarchand): Add support for the PGU (update) phase.
   chrome_pgo_phase = 0
+}
 
+declare_args() {
   # Whether or not the official builds should be built with full WPO. Enabled by
   # default for the PGO and the x64 builds.
   if (chrome_pgo_phase > 0 || target_cpu == "x64") {
@@ -37,18 +56,13 @@ declare_args() {
   } else {
     full_wpo_on_official = false
   }
+}
 
-  # use_debug_fission: whether to use split DWARF debug info
-  # files. This can reduce link time significantly, but is incompatible
-  # with some utilities such as icecc and ccache. Requires gold and
-  # gcc >= 4.8 or clang.
-  # http://gcc.gnu.org/wiki/DebugFission
-  #
-  # This is a placeholder value indicating that the code below should set
-  # the default.  This is necessary to delay the evaluation of the default
-  # value expression until after its input values such as use_gold have
-  # been set, e.g. by a toolchain_args() block.
-  use_debug_fission = "default"
+declare_args() {
+  # Generate Syzygy optimized binaries. Syzygy optimize mode is a profile
+  # guided optimization that reorders code for better locality.
+  syzygy_optimize = is_win && target_cpu == "x86" && is_official_build &&
+                    !is_clang && !is_win_fastlink && symbol_level == 2
 }
 
 declare_args() {