Move ColorChooser{,Client} and DateTimeChooser{,Client} from platform to core.

Source/core/html/forms/DateTimeChooser.h

Index: Source/core/html/forms/DateTimeChooser.h
diff --git a/Source/platform/DateTimeChooser.h b/Source/core/html/forms/DateTimeChooser.h
similarity index 95%
rename from Source/platform/DateTimeChooser.h
rename to Source/core/html/forms/DateTimeChooser.h
index d85c3314d065391cc92c95c83df56b6f8ed09941..c040bfae2cf507a4ccad52fdf939fd04e22b00b9 100644
--- a/Source/platform/DateTimeChooser.h
+++ b/Source/core/html/forms/DateTimeChooser.h
@@ -31,7 +31,6 @@
 #ifndef DateTimeChooser_h
 #define DateTimeChooser_h
 
-#include "platform/PlatformExport.h"
 #include "platform/geometry/IntRect.h"
 #include "wtf/RefCounted.h"
 #include "wtf/text/WTFString.h"
@@ -64,7 +63,7 @@ struct DateTimeChooserParameters {
 };
 
 // For pickers like color pickers and date pickers.
-class PLATFORM_EXPORT DateTimeChooser : public RefCounted<DateTimeChooser> {
+class DateTimeChooser : public RefCounted<DateTimeChooser> {
 public:
     virtual ~DateTimeChooser();