Fix trailing whitespace in .cpp, .h, and .idl files (ex. Source/core)

Source/wtf/text/StringConcatenate.h

Index: Source/wtf/text/StringConcatenate.h
diff --git a/Source/wtf/text/StringConcatenate.h b/Source/wtf/text/StringConcatenate.h
index 5691766e89ac26f7703433ef6d938332f7cd44cc..54088e9698a0256b7e5c184557eec33cc70e4707 100644
--- a/Source/wtf/text/StringConcatenate.h
+++ b/Source/wtf/text/StringConcatenate.h
@@ -20,7 +20,7 @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef StringConcatenate_h
@@ -371,7 +371,7 @@ public:
         const LChar* data = m_buffer.characters8();
         for (unsigned i = 0; i < length; ++i)
             destination[i] = data[i];
-        
+
         WTF_STRINGTYPEADAPTER_COPIED_WTF_STRING();
     }
 
@@ -388,7 +388,7 @@ public:
             for (unsigned i = 0; i < length; ++i)
                 destination[i] = data[i];
         }
-        
+
         WTF_STRINGTYPEADAPTER_COPIED_WTF_STRING();
     }