Enable incremental linking in release component builds

build/config/win/BUILD.gn

Index: build/config/win/BUILD.gn
diff --git a/build/config/win/BUILD.gn b/build/config/win/BUILD.gn
index 48ac47e28a1bcc374fb14e4ed21592160749df26..fb04d41b46ecb27f82a7d2ac14b82ba73d62611f 100644
--- a/build/config/win/BUILD.gn
+++ b/build/config/win/BUILD.gn
@@ -102,7 +102,7 @@ config("compiler") {
   # by about 5%) but does not otherwise alter the output binary. This
   # information is used by the Syzygy optimization tool when decomposing the
   # release image.
-  if (!is_debug && !is_win_fastlink && !is_clang) {
+  if (!is_debug && !is_win_fastlink && !is_clang && !is_component_build) {

[Peter Kasting, 2016/09/14 01:15:17]

Should this match the condition on line 317?  I'm wondering if we should still
have this flag for the "is_syzyasan" case since we don't incrementally link in
that case anyway.

[brucedawson, 2016/09/14 17:49:25]

I had been thinking that it didn't really matter - not all combinations of the
flags are supported or used - but special casing syzyasan is easy enough.

Done.

     ldflags = [ "/PROFILE" ]
   }
 
@@ -312,8 +312,9 @@ config("windowed") {
 incremental_linking_on_switch = [ "/INCREMENTAL" ]
 incremental_linking_off_switch = [ "/INCREMENTAL:NO" ]
 
-# Disable incremental linking for syzyasan
-if (is_debug && !is_syzyasan) {
+# Disable incremental linking for syzyasan, enable for debug builds and all
+# component builds - any builds where performance is not job one.
+if ((is_debug || is_component_build) && !is_syzyasan) {
   default_incremental_linking_switch = incremental_linking_on_switch
 } else {
   default_incremental_linking_switch = incremental_linking_off_switch