Match renaming of ExternalAsciiStringResource.

V8 has removed the ExternalAsciiStringResource alias for the new type
ExternalOneByteStringResource. One-byte strings have Latin-1 encoding,
which is a superset of ASCII, so it's still okay to store ASCII strings
in it.

Change-Id: I54a1c539b004d4ad9073d8a94d7918bf847e8132
diff --git a/src/proxy_resolver_v8.cc b/src/proxy_resolver_v8.cc
index dcd27a1..4d43253 100644
--- a/src/proxy_resolver_v8.cc
+++ b/src/proxy_resolver_v8.cc
@@ -116,7 +116,8 @@
 };
 
 // External string wrapper so V8 can access a string literal.
-class V8ExternalASCIILiteral : public v8::String::ExternalAsciiStringResource {
+class V8ExternalASCIILiteral
+    : public v8::String::ExternalOneByteStringResource {
  public:
   // |ascii| must be a NULL-terminated C string, and must remain valid
   // throughout this object's lifetime.