Rework default GN symbol handling for win goma builds.

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 2e5072e2589133090ed96f857b216186ee3a6836..9f59f84f64560a9cf867eaa31ee52b13b737181d 100644
--- a/build/config/compiler/compiler.gni
+++ b/build/config/compiler/compiler.gni
@@ -82,6 +82,13 @@ if (symbol_level == -1) {
     # With instrumentation enabled, debug info puts libchrome.so over 4gb, which
     # causes the linker to produce an invalid ELF. http://crbug.com/574476
     symbol_level = 0
+  } else if (is_win && use_goma && !is_clang) {
+    # goma doesn't support PDB files, so we disable symbols during goma
+    # compilation because otherwise the redundant debug information generated
+    # by visual studio (repeated in every .obj file) makes linker
+    # memory consumption and link times unsustainable (crbug.com/630074).
+    # Clang on windows does not have this issue.
+    symbol_level = 1
   } else if (!is_linux || is_debug || is_official_build || is_chromecast) {
     # Linux is slowed by having symbols as part of the target binary, whereas
     # Mac and Windows have them separate, so in Release Linux, default them off,