[Autofill] Remove longest common prefix from field names when running heuristics.

components/autofill/core/browser/autofill_field.h

Index: components/autofill/core/browser/autofill_field.h
diff --git a/components/autofill/core/browser/autofill_field.h b/components/autofill/core/browser/autofill_field.h
index 9aaf9fcdfae7d89471df1c46d6e319e2a99e993b..8295440e822399546488b52305ac3e893819de29 100644
--- a/components/autofill/core/browser/autofill_field.h
+++ b/components/autofill/core/browser/autofill_field.h
@@ -40,6 +40,7 @@ class AutofillField : public FormFieldData {
   const ServerFieldTypeSet& possible_types() const { return possible_types_; }
   PhonePart phone_part() const { return phone_part_; }
   bool previously_autofilled() const { return previously_autofilled_; }
+  const base::string16& parseable_name() const { return parseable_name_; }
 
   // Setters for the detected type and section for this field.
   void set_section(const std::string& section) { section_ = section; }
@@ -52,6 +53,9 @@ class AutofillField : public FormFieldData {
   void set_previously_autofilled(bool previously_autofilled) {
     previously_autofilled_ = previously_autofilled;
   }
+  void set_parseable_name(const base::string16& parseable_name) {

[vabr (Chromium), 2016/01/25 10:10:25]

nit: passing by value and using std::move is potentially avoiding a copy:

case 1 -- if the argument is a temporary, then passing by value + move makes 0
copies, unlike the current code

case 2 -- otherwise, there is 1 copy in both versions of code (only it happens
during calling with pass by value + move, and on line 57 in the current code)

[Mathieu, 2016/01/25 15:52:53]

Done.

+    parseable_name_ = parseable_name;
+  }
 
   // This function automatically chooses between server and heuristic autofill
   // type, depending on the data available.
@@ -139,6 +143,11 @@ class AutofillField : public FormFieldData {
   // Whether the field was autofilled then later edited.
   bool previously_autofilled_;
 
+  // The parseable name attribute, with unnecessary information removed (such as
+  // a common prefix shared with other fields). Will be used for heuristics
+  // parsing.
+  base::string16 parseable_name_;
+
   DISALLOW_COPY_AND_ASSIGN(AutofillField);
 };