Turn v8.h into a normal header.

src/DEPS

Index: src/DEPS
diff --git a/src/DEPS b/src/DEPS
index 4b95456a17d618b02394ddc740d23e4af4a60ad0..7350f61f9f2b755481502b2e201e535055da25e2 100644
--- a/src/DEPS
+++ b/src/DEPS
@@ -14,9 +14,10 @@ include_rules = [
 
 specific_include_rules = {
   ".*\.h": [
-    # Note that src/v8.h is the top header for some .cc files, it shouldn't be
-    # included in any .h files though. In the long run we should make src/v8.h
-    # act like any normal header file, instead of a grab-bag include.
+    # 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": [