MIPS: Make kAsciiDataHintTag have correct semantics for all both 1 and 2 byte string types.

src/mips/macro-assembler-mips.cc

Index: src/mips/macro-assembler-mips.cc
diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index 11c641d93afcdcc9b0651bb2d39422f44b6b7659..8293a100282b1519de3b65648796c55268475a2d 100644
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -4896,8 +4896,10 @@ void MacroAssembler::JumpIfBothInstanceTypesAreNotSequentialAscii(
     Register scratch2,
     Label* failure) {
   int kFlatAsciiStringMask =
-      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
+      kIsNotStringMask | kStringEncodingMask | kAsciiDataHintMask |
+      kStringRepresentationMask;
   int kFlatAsciiStringTag = ASCII_STRING_TYPE;
+  ASSERT_EQ(ASCII_STRING_TYPE, ASCII_STRING_TYPE & kFlatAsciiStringMask);
   ASSERT(kFlatAsciiStringTag <= 0xffff);  // Ensure this fits 16-bit immed.
   andi(scratch1, first, kFlatAsciiStringMask);
   Branch(failure, ne, scratch1, Operand(kFlatAsciiStringTag));
@@ -4910,8 +4912,10 @@ void MacroAssembler::JumpIfInstanceTypeIsNotSequentialAscii(Register type,
                                                             Register scratch,
                                                             Label* failure) {
   int kFlatAsciiStringMask =
-      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
+      kIsNotStringMask | kStringEncodingMask | kAsciiDataHintMask |
+      kStringRepresentationMask;
   int kFlatAsciiStringTag = ASCII_STRING_TYPE;
+  ASSERT_EQ(ASCII_STRING_TYPE, ASCII_STRING_TYPE & kFlatAsciiStringMask);
   And(scratch, type, Operand(kFlatAsciiStringMask));
   Branch(failure, ne, scratch, Operand(kFlatAsciiStringTag));
 }