Fixing a comment and vector type. (facebookincubator#10410)

Summary:
Pull Request resolved: facebookincubator#10410

- Fixing a comment.
- Reducing hard coded vector types as max hard coded value can be limited to smaller types.

Differential Revision: D59424733

velox/functions/lib/string/StringCore.h

@@ -359,7 +359,7 @@ inline int64_t findNthInstanceByteIndexFromEnd(
 
 /// Replace replaced with replacement in inputString and write results in
 /// outputString. If inPlace=true inputString and outputString are assumed to
-/// tbe the same. When replaced is empty and ignoreEmptyReplaced is false,
+/// be the same. When replaced is empty and ignoreEmptyReplaced is false,
 /// replacement is added before and after each charecter. When replaced is
 /// empty and ignoreEmptyReplaced is true, the result is the inputString value.
 /// When inputString is empty results is empty.

velox/functions/lib/string/StringImpl.h

@@ -309,7 +309,7 @@ FOLLY_ALWAYS_INLINE bool md5_radix(
 
 namespace {
 FOLLY_ALWAYS_INLINE int64_t asciiWhitespaces() {
-  std::vector<int32_t> codes = {9, 10, 11, 12, 13, 28, 29, 30, 31, 32};
+  int8_t codes[] = {9, 10, 11, 12, 13, 28, 29, 30, 31, 32};
   int64_t bitMask = 0;
   for (auto code : codes) {
     bits::setBit(&bitMask, code, true);
@@ -318,7 +318,7 @@ FOLLY_ALWAYS_INLINE int64_t asciiWhitespaces() {
 }
 
 FOLLY_ALWAYS_INLINE int64_t asciiWhitespaceCodes() {
-  std::vector<int32_t> codes = {9, 10, 11, 12, 13, 28, 29, 30, 31, 32};
+  int8_t codes[] = {9, 10, 11, 12, 13, 28, 29, 30, 31, 32};
   int64_t bitMask = 0;
   for (auto code : codes) {
     bits::setBit(&bitMask, code, true);
@@ -327,7 +327,7 @@ FOLLY_ALWAYS_INLINE int64_t asciiWhitespaceCodes() {
 }
 
 FOLLY_ALWAYS_INLINE std::array<int64_t, 2> unicodeWhitespaceCodes() {
-  std::vector<int32_t> codes = {
+  int16_t codes[] = {
       8192,
       8193,
       8194,