[Password Generation] Sends form classifier vote to autofill server

components/autofill/core/browser/proto/server.proto

Index: components/autofill/core/browser/proto/server.proto
diff --git a/components/autofill/core/browser/proto/server.proto b/components/autofill/core/browser/proto/server.proto
index 7dec36bd0e900e0cd689bd0e3cbecdd7024ff98d..46bbfdb8ff88b8f27ecd927eaeacfc005560faaf 100644
--- a/components/autofill/core/browser/proto/server.proto
+++ b/components/autofill/core/browser/proto/server.proto
@@ -34,7 +34,7 @@ message AutofillQueryResponseContents {
 
 // This message contains information about the field types in a single form.
 // It is sent by the toolbar to contribute to the field type statistics.
-// Next available id: 18
+// Next available id: 19
 message AutofillUploadContents {
   required string client_version = 1;
   required fixed64 form_signature = 2;
@@ -83,6 +83,14 @@ message AutofillUploadContents {
     }
     // The type of password generation, if it happened.
     optional PasswordGenerationType generation_type = 17;
+
+    enum FormClassifierOutcome {
+      NO_OUTCOME = 0;
+      NON_GENERATION_ELEMENT = 1;
+      GENERATION_ELEMENT = 2;
+    }
+    // The outcome of HTML parsing based form classifier.
+    optional FormClassifierOutcome form_classifier_outcome = 18;
   }
   // Signature of the form action host (e.g. Hash64Bit("example.com")).
   optional fixed64 action_signature = 13;