Remove url::ReadUTFChar's dependency on icu. Use base instead.

url/url_canon_internal.h

Index: url/url_canon_internal.h
===================================================================
--- url/url_canon_internal.h	(revision 266896)
+++ url/url_canon_internal.h	(working copy)
@@ -148,8 +148,6 @@
 // |*begin| will be updated to point to the last character consumed so it
 // can be incremented in a loop and will be ready for the next character.
 // (for a single-byte ASCII character, it will not be changed).
-//
-// Implementation is in url_canon_icu.cc.
 URL_EXPORT bool ReadUTFChar(const char* str, int* begin, int length,
                             unsigned* code_point_out);
 
@@ -225,10 +223,8 @@
 // |*begin| will be updated to point to the last character consumed so it
 // can be incremented in a loop and will be ready for the next character.
 // (for a single-16-bit-word character, it will not be changed).
-//
-// Implementation is in url_canon_icu.cc.
 URL_EXPORT bool ReadUTFChar(const base::char16* str, int* begin, int length,
-                            unsigned* code_point);
+                            unsigned* code_point_out);
 
 // Equivalent to U16_APPEND_UNSAFE in ICU but uses our output method.
 inline void AppendUTF16Value(unsigned code_point,