Allow incrementally linked release builds on windows.

build/release.gypi

 {
   'conditions': [
     # Handle build types.
     ['buildtype=="Dev"', {
       'includes': ['internal/release_impl.gypi'],
     }],
+    ['buildtype=="Dev" and incremental_chrome_dll==1', {
+      'msvs_settings': {
+        'VCLinkerTool': {
+          # Enable incremental linking and disable conflicting link options:
+          # http://msdn.microsoft.com/en-us/library/4khtbfyf.aspx
+          'LinkIncremental': '2',
+          'OptimizeReferences': '1',
+          'EnableCOMDATFolding': '1',
+          'Profile': 'false',
+        },
+      },
+    }],
     ['buildtype=="Official"', {
       'includes': ['internal/release_impl_official.gypi'],
     }],
     # TODO(bradnelson): may also need:
     #     checksenabled
     #     coverage
     #     dom_stats
     #     pgo_instrument
     #     pgo_optimize
   ],
 }