Move v8_optimized_debug default value to standalone.gypi

build/toolchain.gypi

Index: build/toolchain.gypi
diff --git a/build/toolchain.gypi b/build/toolchain.gypi
index c1066ebe94b7697968d211e5e98b6dc7ff747c9d..e1903f300fd757090f123a16f7456880b9779748 100644
--- a/build/toolchain.gypi
+++ b/build/toolchain.gypi
@@ -60,20 +60,6 @@
 
     'v8_enable_backtrace%': 0,
 
-    # Speeds up Debug builds:
-    # 0 - Compiler optimizations off (debuggable) (default). This may
-    #     be 5x slower than Release (or worse).
-    # 1 - Turn on compiler optimizations. This may be hard or impossible to
-    #     debug. This may still be 2x slower than Release (or worse).
-    # 2 - Turn on optimizations, and also #undef DEBUG / #define NDEBUG
-    #     (but leave V8_ENABLE_CHECKS and most other assertions enabled.
-    #     This may cause some v8 tests to fail in the Debug configuration.
-    #     This roughly matches the performance of a Release build and can
-    #     be used by embedders that need to build their own code as debug
-    #     but don't want or need a debug version of V8. This should produce
-    #     near-release speeds.
-    'v8_optimized_debug%': 0,
-
     # Enable profiling support. Only required on Windows.
     'v8_enable_prof%': 0,