Fix bug in Utf8::CodePointCount which was causing some strings with latin1

vm/unicode.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/unicode.h"
 
 #include "vm/allocation.h"
 #include "vm/globals.h"
 #include "vm/object.h"
 
@@ skipping 35 matching lines @@
   0,  // Padding.
   0x0,
   0x80,
   0x800,
   0x10000,
   0xFFFFFFFF,
   0xFFFFFFFF
 };
 
 
-// Returns a count of the number of UTF-8 trail bytes.
-intptr_t Utf8::CodePointCount(const uint8_t* utf8_array,
-                              intptr_t array_len,
-                              Type* type) {
+// Returns the most restricted coding form in which the sequence of utf8
+// characters in 'utf8_array' can be represented in, and the number of
+// code units needed in that form.
+intptr_t Utf8::CodeUnitCount(const uint8_t* utf8_array,
+                             intptr_t array_len,
+                             Type* type) {
   intptr_t len = 0;
   Type char_type = kLatin1;
   for (intptr_t i = 0; i < array_len; i++) {
     uint8_t code_unit = utf8_array[i];
     if (!IsTrailByte(code_unit)) {
       ++len;
-    }
-    if (!IsLatin1SequenceStart(code_unit)) {  // > U+00FF
-      if (IsSupplementarySequenceStart(code_unit)) {  // >= U+10000
-        char_type = kSupplementary;
-        ++len;
-      } else if (char_type == kLatin1) {
-        char_type = kBMP;
+      if (!IsLatin1SequenceStart(code_unit)) {  // > U+00FF
+        if (IsSupplementarySequenceStart(code_unit)) {  // >= U+10000
+          char_type = kSupplementary;
+          ++len;
+        } else if (char_type == kLatin1) {
+          char_type = kBMP;
+        }
       }
     }
   }
   *type = char_type;
   return len;
 }
 
 
 // Returns true if str is a valid NUL-terminated UTF-8 string.
 bool Utf8::IsValid(const uint8_t* utf8_array, intptr_t array_len) {
@@ skipping 211 matching lines @@
 
 
 void Utf16::Encode(int32_t codepoint, uint16_t* dst) {
   ASSERT(codepoint > Utf16::kMaxCodeUnit);
   ASSERT(dst != NULL);
   dst[0] = (Utf16::kLeadSurrogateOffset + (codepoint >> 10));
   dst[1] = (0xDC00 + (codepoint & 0x3FF));
 }
 
 }  // namespace dart