Remove several grab-bag includes from the v8.h header.

src/DEPS

Index: src/DEPS
diff --git a/src/DEPS b/src/DEPS
index 021cd3bf2d94c0fece6769fc60111ee5c12d3b67..37becca773b8579577ed85ebde38feed5a79c0b2 100644
--- a/src/DEPS
+++ b/src/DEPS
@@ -13,6 +13,12 @@ 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.
+    "-src/v8.h",
+  ],
   "d8\.cc": [
     "+include/libplatform/libplatform.h",
   ],