Add mojo_view_manager -> skia dep

Fixes windows component error since we use SkMatrix in DrawViewTree.

BUG=413727

Review URL: https://codereview.chromium.org/566933003

Cr-Commit-Position: refs/heads/master@{#294625}

mojo/mojo_services.gypi

@@ -703,6 +703,7 @@
           'dependencies': [
             '../base/base.gyp:base',
             '../cc/cc.gyp:cc_surfaces',
+            '../skia/skia.gyp:skia',
             '../ui/base/ui_base.gyp:ui_base',
             '../ui/events/events.gyp:events',
             '../ui/events/events.gyp:events_base',