Perform input validation on the AutoFill profile editor.

Perform some simple input validation on the autofill profile
editor to match Chromium's editor more closely.

Now:
- Phone number must be at least 7 digits if present
- Cannot save an empty profile. At least one field other than
phone number must be present and if phone number is present it must be
valid.

Bug:3349013
Bug:3198461
Change-Id: I6d277dda2264c5cebd0b525b1c4cdb80313383ec
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 9771e18..05042db 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -410,6 +410,8 @@
     <string name="autofill_profile_editor_country">Country:</string>
     <!-- String for the user's phone number in the AutoFill profile editor. [CHAR-LIMIT=32] -->
     <string name="autofill_profile_editor_phone_number">Phone:</string>
+    <!-- String to display in an error tooltip to inform the user the phone number they provided is not valid. [CHAR-LIMIT=32] -->
+    <string name="autofill_profile_editor_phone_number_invalid">Invalid phone number</string>
 
     <!-- Button text to save the AutoFill profile [CHAR-LIMIT=20] -->
     <string name="autofill_profile_editor_save_profile">Save profile</string>