[build] Disable incremental linking for cctest and unittests

gni/v8.gni

Index: gni/v8.gni
diff --git a/gni/v8.gni b/gni/v8.gni
index 7ff7f6fb89ac3634a2c7ff64030805582d8c8fb9..f36966dc9451863c5c9303980cf8323de00cc122 100644
--- a/gni/v8.gni
+++ b/gni/v8.gni
@@ -95,6 +95,10 @@ template("v8_executable") {
       # For enabling ASLR.
       ldflags = [ "-pie" ]
     }
+    if (defined(no_incremental_linking) && no_incremental_linking && is_win) {

[vogelheim, 2016/10/11 13:11:37]

I thought "defined(X) && X" was an anti-pattern that we're trying to avoid. Why
is this necessary here?

[Michael Achenbach, 2016/10/12 07:32:08]

That's how templates seem to be designed. There's no way of providing default
values. Many places in src/build actually move most fields into additional local
variables like:
https://cs.chromium.org/chromium/src/build/config/ios/rules.gni?q=template+fi...

Then we'd get the pattern:
foo = default_foo
if (defined(invoker.foo)) {
  foo = invoker.foo
}
if (foo) ...

Not sure if that's better. That's basically the same with more boilerplate.

If we want to get around the "defined" check, we'd need to write the variable in
each of the template invocations, e.g. d8, all fuzzers, etc.

See also
https://chromium.googlesource.com/chromium/src/+/master/tools/gn/docs/referen...

+      configs -= [ "//build/config/win:default_incremental_linking" ]
+      configs += [ "//build/config/win:no_incremental_linking" ]
+    }
   }
 }