[Autofill] Autofill internals log if a field is empty.

Change-Id: Ie055b7b2a4c09122cc6bae6caa778a8b4677f4a6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2230489Reviewed-by: Dominic Battré <battre@chromium.org>
Commit-Queue: Matthias Körber <koerber@google.com>
Auto-Submit: Matthias Körber <koerber@google.com>
Cr-Commit-Position: refs/heads/master@{#775211}

components/autofill/core/browser/form_structure.cc

@@ -2328,6 +2328,8 @@ std::ostream& operator<<(std::ostream& buffer, const FormStructure& form) {
     const base::string16 truncated_label =
         field->label.substr(0, std::min(field->label.length(), kMaxLabelSize));
     buffer << "\n  Label: " << truncated_label;
+
+    buffer << "\n  Is empty: " << (field->IsEmpty() ? "Yes" : "No");
   }
   return buffer;
 }
@@ -2372,6 +2374,8 @@ LogBuffer& operator<<(LogBuffer& buffer, const FormStructure& form) {
     const base::string16 truncated_label =
         field->label.substr(0, std::min(field->label.length(), kMaxLabelSize));
     buffer << Tr{} << "Label:" << truncated_label;
+
+    buffer << Tr{} << "Is empty:" << (field->IsEmpty() ? "Yes" : "No");
     buffer << CTag{"table"};
     buffer << CTag{"td"};
     buffer << CTag{"tr"};

components/autofill/core/common/form_field_data.cc

@@ -441,6 +441,7 @@ LogBuffer& operator<<(LogBuffer& buffer, const FormFieldData& field) {
   buffer << Tr{} << "Is focusable:" << field.is_focusable;
   buffer << Tr{} << "Is enabled:" << field.is_enabled;
   buffer << Tr{} << "Is readonly:" << field.is_readonly;
+  buffer << Tr{} << "Is empty:" << (field.value.empty() ? "Yes" : "No");
   buffer << CTag{"table"};
   return buffer;
 }