Canonicalize uris in C++ instead of Dart for the standalone embedder.

runtime/vm/zone.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/zone.h"
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/flags.h"
 #include "vm/handles_impl.h"
@@ skipping 151 matching lines @@
 
 
 char* Zone::MakeCopyOfString(const char* str) {
   intptr_t len = strlen(str) + 1;  // '\0'-terminated.
   char* copy = Alloc<char>(len);
   strncpy(copy, str, len);
   return copy;
 }
 
 
+char* Zone::MakeCopyOfStringN(const char* str, intptr_t len) {
+  ASSERT(len >= 0);
+  for (intptr_t i = 0; i < len; i++) {
+    if (str[i] == '\0') {
+      len = i;
+      break;
+    }
+  }
+  char* copy = Alloc<char>(len + 1);  // +1 for '\0'
+  strncpy(copy, str, len);
+  copy[len] = '\0';
+  return copy;
+}
+
+
 char* Zone::ConcatStrings(const char* a, const char* b, char join) {
   intptr_t a_len = (a == NULL) ? 0 : strlen(a);
   const intptr_t b_len = strlen(b) + 1;  // '\0'-terminated.
   const intptr_t len = a_len + b_len;
   char* copy = Alloc<char>(len);
   if (a_len > 0) {
     strncpy(copy, a, a_len);
     // Insert join character.
     copy[a_len++] = join;
   }
@@ skipping 30 matching lines @@
   return buffer;
 }
 
 
 char* Zone::VPrint(const char* format, va_list args) {
   return OS::VSCreate(this, format, args);
 }
 
 
 }  // namespace dart