managing chromes use section of docs

site/dev/chrome/changes.md

+Landing Skia changes which require associated Chrome changes
+============================================================
+
+If your change modifies the Skia API, you may also need to land a change in Chromium.
+
+The strategy you use to synchronize changes in the Skia and Chromium
+repositories may differ based on the nature of the change, but in general, we
+recommend using build flag suppressions \(defines\)\.
+We also prefer making the old code path opt-in where possible.
+
+Method 1 \(preferred\) \- Make the old code path opt\-in for Chromium
+  
+  * Add new code to Skia, leaving the old code in place.
+  * Deprecate the old code path so that it must be enabled with a flag such as
+    'SK_SUPPORT_LEGACY_XXX'.
+  * Synchronize the above changes in Skia with a Chromium commit to
+    'skia/skia_common.gypi' or 'skia/config/SkUserConfig.h' to enable the 
+    deprecated Skia API.
+      * Note that the code suppression cannot exist in both the header file and
+      the gyp file, it should only reside in one location.
+  * Test the new or updated Skia API within Chromium.
+  * Remove the flag and code when the legacy code path is no longer in use.
+
+Method 2 \- Make the new code path opt\-in for Chromium
+
+  * Add new code to Skia, suppressed by a flag.
+  * Leave the old code path in place.
+  * Set the flag in Chromium's 'skia/skia_common.gypi' or 
+    'skia/config/SkUserConfig.h' to enable the new or updated Skia API.
+  * Test the new or updated Skia API within Chromium.
+  * Remove the code suppression \(and code\) when the legacy API is no longer 
+    in use.
+
+If your changes will affect Blink layout tests, see detailed instructions about
+how to synchronize the changes between Skia, Blink, and Chromium [here](./blink).