Implement wxString::Shrink() in terms of shrink_to_fit()

Now that we use C++11 there is no need to have our own Shrink()
implementation when we can just use the standard function.

Also mention that it's the same as shrink_to_fit() in Shrink()
documentation.

No real changes, just simplify the code and make it more efficient.

include/wx/string.h

@@ -1368,7 +1368,7 @@ class WXDLLIMPEXP_BASE wxString
   size_type capacity() const { return m_impl.capacity(); }
   void reserve(size_t sz) { m_impl.reserve(sz); }
 
-  void shrink_to_fit() { Shrink(); }
+  void shrink_to_fit() { m_impl.shrink_to_fit(); }
 
   void resize(size_t nSize, wxUniChar ch = wxT('\0'))
   {
@@ -2241,8 +2241,7 @@ class WXDLLIMPEXP_BASE wxString
     // only works if the data of this string is not shared
   bool Alloc(size_t nLen) { reserve(nLen); return capacity() >= nLen; }
     // minimize the string's memory
-    // only works if the data of this string is not shared
-  bool Shrink();
+  bool Shrink() { shrink_to_fit(); return true; }
 
   // wxWidgets version 1 compatibility functions
 

interface/wx/string.h

@@ -1422,7 +1422,7 @@ class wxString
         wxStringBuffer and wxStringBufferLength classes may be very useful when working
         with some external API which requires the caller to provide a writable buffer.
 
-        See also the reserve() and resize() STL-like functions.
+        See also the reserve(), resize() and shrink_to_fit() STL-like functions.
     */
     ///@{
 
@@ -1468,6 +1468,9 @@ class wxString
     /**
         Minimizes the string's memory.
 
+        Please note that this method does the same thing as the standard
+        shrink_to_fit() one and shouldn't be used in new code.
+
         This can be useful after a call to Alloc() if too much memory were
         preallocated.
 

src/common/string.cpp

@@ -514,14 +514,6 @@ const char *wxString::AsChar(const wxMBConv& conv) const
     return m_convertedToChar.m_str;
 }
 
-// shrink to minimal size (releasing extra memory)
-bool wxString::Shrink()
-{
-  wxString tmp(begin(), end());
-  swap(tmp);
-  return true;
-}
-
 // ---------------------------------------------------------------------------
 // data access
 // ---------------------------------------------------------------------------