Don't set v8_optimized_debug as default value, but as actual value

Otherwise, it doesn't have any effect, because it collides with the
default value set already by v8

BUG=none
TBR=danno@chromium.org

Review URL: https://codereview.chromium.org/19192003

git-svn-id: http://src.chromium.org/svn/trunk/src/build@211782 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -1109,7 +1109,7 @@
     'enable_rlz%': 0,
 
     # Turns on compiler optimizations in V8 in Debug build.
-    'v8_optimized_debug%': 1,
+    'v8_optimized_debug': 1,
 
     'conditions': [
       # The version of GCC in use, set later in platforms that use GCC and have