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

Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp

Index: Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp
diff --git a/Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp b/Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp
index eb2c91e14acab846a4804688d02e1fe88fc04d1c..089253df4e2b5db43d6df26bb2b894b02ca4f1db 100644
--- a/Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp
+++ b/Source/bindings/v8/custom/V8HTMLMediaElementCustom.cpp
@@ -43,7 +43,7 @@ void V8HTMLMediaElement::controllerAttrSetterCustom(v8::Local<v8::String>, v8::L
     }
 
     // 4.8.10.11.2 Media controllers: controller attribute.
-    // On setting, it must first remove the element's mediagroup attribute, if any, 
+    // On setting, it must first remove the element's mediagroup attribute, if any,
     HTMLMediaElement* imp = V8HTMLMediaElement::toNative(info.Holder());
     imp->setMediaGroup(String());
     // and then set the current media controller to the given value.