Declare dependency on blink_headers in targets that use blink headers

content/content_browser.gypi

Index: content/content_browser.gypi
diff --git a/content/content_browser.gypi b/content/content_browser.gypi
index 6345f6b7834d4904af01880f8bc85ef47d607af6..f10a0c240dd6c3cc235a3aa782cd404e80d19a83 100644
--- a/content/content_browser.gypi
+++ b/content/content_browser.gypi
@@ -13,6 +13,7 @@
     '../sql/sql.gyp:sql',
     '../third_party/zlib/google/zip.gyp:zip',
     '../third_party/zlib/zlib.gyp:zlib',
+    '../third_party/WebKit/public/blink.gyp:blink_headers',
     '../ui/accessibility/accessibility.gyp:accessibility',
     '../ui/events/events.gyp:events_base',
     '../ui/events/events.gyp:gesture_detection',
@@ -27,6 +28,12 @@
     '..',
     '<(INTERMEDIATE_DIR)',
   ],
+  'export_dependent_settings': [
+    # The public content API headers directly include Blink API headers, so we
+    # have to export the blink header settings so that relative paths in these
+    # headers resolve correctly.
+    '../third_party/WebKit/public/blink.gyp:blink_headers',
+  ],
   'sources': [
     'port/browser/event_with_latency_info.h',
     'port/browser/location_provider.h',