Fix MSVC-64 warnings about size_t -> int truncations in C++-lib.

Change-Id: Ibe6f41ac15df1ec685b0d0766ff568abf6f3ae7e
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/3rdparty/cplusplus/Control.cpp

@@ -584,7 +584,7 @@ const Identifier *Control::identifier(const char *chars, unsigned size)
 
 const Identifier *Control::identifier(const char *chars)
 {
-    unsigned length = std::strlen(chars);
+    const unsigned length = unsigned(std::strlen(chars));
     return identifier(chars, length);
 }
 
@@ -611,7 +611,7 @@ const StringLiteral *Control::stringLiteral(const char *chars, unsigned size)
 
 const StringLiteral *Control::stringLiteral(const char *chars)
 {
-    unsigned length = std::strlen(chars);
+    const unsigned length = unsigned(std::strlen(chars));
     return stringLiteral(chars, length);
 }
 
@@ -620,7 +620,7 @@ const NumericLiteral *Control::numericLiteral(const char *chars, unsigned size)
 
 const NumericLiteral *Control::numericLiteral(const char *chars)
 {
-    unsigned length = std::strlen(chars);
+    const unsigned length = unsigned(std::strlen(chars));
     return numericLiteral(chars, length);
 }