Fix a gcc 4.6 compiler warning.

patches/gcc4.6.patch

Index: patches/gcc4.6.patch
diff --git a/patches/gcc4.6.patch b/patches/gcc4.6.patch
new file mode 100644
index 0000000000000000000000000000000000000000..2dac69ea5c9231f3347ec7de6232b5ad4588cdde
--- /dev/null
+++ b/patches/gcc4.6.patch
@@ -0,0 +1,24 @@
+diff --git source/common/unicode/unistr.h source/common/unicode/unistr.h
+index 57ea346..46b9d95 100644
+--- source/common/unicode/unistr.h
++++ source/common/unicode/unistr.h
+@@ -4021,8 +4021,7 @@ UnicodeString::replace(int32_t start,
+                UChar32 srcChar) {
+   UChar buffer[U16_MAX_LENGTH];
+   int32_t count = 0;
+-  UBool isError = FALSE;
+-  U16_APPEND(buffer, count, U16_MAX_LENGTH, srcChar, isError);
++  U16_APPEND_UNSAFE(buffer, count, srcChar);
+   return doReplace(start, _length, buffer, 0, count);
+ }
+ 
+@@ -4324,8 +4323,7 @@ inline UnicodeString&
+ UnicodeString::append(UChar32 srcChar) {
+   UChar buffer[U16_MAX_LENGTH];
+   int32_t _length = 0;
+-  UBool isError = FALSE;
+-  U16_APPEND(buffer, _length, U16_MAX_LENGTH, srcChar, isError);
++  U16_APPEND_UNSAFE(buffer, _length, srcChar);
+   return doReplace(length(), 0, buffer, 0, _length);
+ }
+