Use base::StartWith() in more places when appropriate.

components/autofill/core/browser/autofill_profile_comparator.cc

Index: components/autofill/core/browser/autofill_profile_comparator.cc
diff --git a/components/autofill/core/browser/autofill_profile_comparator.cc b/components/autofill/core/browser/autofill_profile_comparator.cc
index d4c500308a85a77b669e972a8e9d4aae67e4b97c..38831cd4b04dc2c623020d88a3d3223f8733280a 100644
--- a/components/autofill/core/browser/autofill_profile_comparator.cc
+++ b/components/autofill/core/browser/autofill_profile_comparator.cc
@@ -309,7 +309,7 @@ bool AutofillProfileComparator::MergePhoneNumbers(
   // include the country code prefix.
   if (merged_number.country_code() == 1 &&
       merged_number.national_number() <= 9999999 &&
-      new_number.find("+1") == 0) {
+      base::StartsWith(new_number, "+1", base::CompareCase::SENSITIVE)) {
     size_t offset = 2;  // The char just after "+1".
     while (offset < new_number.size() &&
            base::IsAsciiWhitespace(new_number[offset])) {