Remove rule prohibiting including src/v8.h

src/DEPS

Index: src/DEPS
diff --git a/src/DEPS b/src/DEPS
index b54cd045634eb281e4c416e1c8a062d567b98fc1..f8a63f0ef951315887240e053d16b233f2e2c545 100644
--- a/src/DEPS
+++ b/src/DEPS
@@ -17,13 +17,6 @@ include_rules = [
 ]
 
 specific_include_rules = {
-  ".*\.h": [
-    # Note that src/v8.h by now is a regular header file, it doesn't provide
-    # any special declarations besides the V8 class. There should be no need
-    # for including it in any .h files though. This rule is just a reminder,
-    # and can be removed once the dust has settled.
-    "-src/v8.h",
-  ],
   "d8\.cc": [
     "+include/libplatform/libplatform.h",
   ],