enable incremental linking by default when using ninja on Windows

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index c836456776266251f8dc54cdbd28b6bc5377d4fd..5d67d11df66dc1b3dfdde4da5f9933df49ec04ec 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -703,7 +703,7 @@
     # Needed for some of the largest modules.
     'msvs_debug_link_nonincremental%': '1',
 
-    # Turn on Use Library Dependency Inputs for linking chrome.dll on Windows
+    # Turns on Use Library Dependency Inputs for linking chrome.dll on Windows
     # to get incremental linking to be faster in debug builds.
     'incremental_chrome_dll%': '0',
 
@@ -1042,6 +1042,10 @@
           ['component=="shared_library"', {
             'win_use_allocator_shim%': 0,
           }],
+          ['"<(GENERATOR)"=="ninja"', {
+            # Only enabled by default for ninja because it's buggy in VS.
+            'incremental_chrome_dll%': 1,
+          }],
           # Whether to use multiple cores to compile with visual studio. This is
           # optional because it sometimes causes corruption on VS 2005.
           # It is on by default on VS 2008 and off on VS 2005.