Rename InterfaceID to ApiID and move the file.

This was originally in the proxy and had a 1:1 correspondence with an
interface. Then we reused this for other stuff and then merged some interfaces
into larger APIs (ppapi/thunk/*_api.h) so the name was no longer accurate.
It was wrong to be in the proxy directory since directories at a "lower level"
than the proxy (ppapi/shared_impl and webkit/plugins/ppapi) depended on it.

This renames to ApiID (I avoided APIID since it looks like a define) which is
the proper description of the class, and moved it to shared_impl. This fixes
the deps since there are no longer any bad dependencies on the proxy directory.

TEST=it compiles
BUG=none

Review URL: http://codereview.chromium.org/8333004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@106619 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/ppapi/proxy/dispatcher.cc b/ppapi/proxy/dispatcher.cc
index 8381c6a..1d8614da 100644
--- a/ppapi/proxy/dispatcher.cc
+++ b/ppapi/proxy/dispatcher.cc
@@ -28,7 +28,7 @@
 Dispatcher::~Dispatcher() {
 }
 
-InterfaceProxy* Dispatcher::GetInterfaceProxy(InterfaceID id) {
+InterfaceProxy* Dispatcher::GetInterfaceProxy(ApiID id) {
   InterfaceProxy* proxy = proxies_[id].get();
   if (!proxy) {
     // Handle the first time for a given API by creating the proxy for it.
@@ -66,13 +66,13 @@
     return handled;
   }
 
-  if (msg.routing_id() <= 0 || msg.routing_id() >= INTERFACE_ID_COUNT) {
+  if (msg.routing_id() <= 0 || msg.routing_id() >= API_ID_COUNT) {
     OnInvalidMessageReceived();
     return true;
   }
 
   InterfaceProxy* proxy = GetInterfaceProxy(
-      static_cast<InterfaceID>(msg.routing_id()));
+      static_cast<ApiID>(msg.routing_id()));
   if (!proxy) {
     NOTREACHED();
     return true;