[Autofill/Autocomplete Feature] Substring matching instead of prefix matching.

components/autofill/core/common/autofill_switches.cc

Index: components/autofill/core/common/autofill_switches.cc
diff --git a/components/autofill/core/common/autofill_switches.cc b/components/autofill/core/common/autofill_switches.cc
index 675475aad5daa5f47fa114d0dcd7b462059847aa..017833550b66749089b217ef6938b5edaffdfd82 100644
--- a/components/autofill/core/common/autofill_switches.cc
+++ b/components/autofill/core/common/autofill_switches.cc
@@ -63,6 +63,10 @@ const char kEnablePasswordGeneration[]      = "enable-password-generation";
 // Enables/disables suggestions without typing anything (on first click).
 const char kEnableSingleClickAutofill[]     = "enable-single-click-autofill";
 
+// Enables suggestions with substring matching instead of prefix matching.
+const char kEnableSuggestionsWithSubstringMatch[] =
+    "enable-suggestions-with-substring-match";
+
 // Enables syncing usage counts and last use dates of Wallet addresses and
 // cards.
 const char kEnableWalletMetadataSync[]      = "enable-wallet-metadata-sync";