Add PrinterSpecifics to the sync protos.

components/sync/protocol/sync.proto

Index: components/sync/protocol/sync.proto
diff --git a/components/sync/protocol/sync.proto b/components/sync/protocol/sync.proto
index 7e28cdab9319b618a0ef10929fbfe201533ac625..bce10192c2d27e48169934041bedfa7d93cf1e38 100644
--- a/components/sync/protocol/sync.proto
+++ b/components/sync/protocol/sync.proto
@@ -41,6 +41,7 @@ import "managed_user_specifics.proto";
 import "managed_user_whitelist_specifics.proto";
 import "password_specifics.proto";
 import "preference_specifics.proto";
+import "printers_specifics.proto";
 import "priority_preference_specifics.proto";
 import "search_engine_specifics.proto";
 import "session_specifics.proto";
@@ -136,6 +137,7 @@ message EntitySpecifics {
   optional AutofillWalletSpecifics autofill_wallet = 306270;
   optional WalletMetadataSpecifics wallet_metadata = 330441;
   optional ArcPackageSpecifics arc_package = 340906;
+  optional PrintersSpecifics printers = 410745;

[Nicolas Zea, 2016/09/13 00:14:06]

I should have been more clear before. This field name should remain printer.
Similarly, the specifics (and the file name) should be PrinterSpecifics.

The enum is all that I meant you should change to PRINTERS previously, as it
describes the set of all entities of that type. The individual entities still
represent a single "printer".

[skau, 2016/09/13 21:02:44]

Okay.  Do you know where this presubmit warning comes from?

Message:
Error at lines 135-136 in model_type.cc: notification type "PRINTERS" does not
match proto message name defined in sync.proto: "printer"

I didn't realize that it was flagging the UMA label and not the enum name.

 }
 
 message SyncEntity {