Bug 210496 Add hasStyle property in reportItemModel extension point
When chart gets reportItem's properties by extending ReportItem, style properties are null. Hence, model needs to add hasStyle property in reportItemModel extension point
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/ElementDefn.java
* <p>
 * Elements are part of a design, and each design has its own set of elements
 * depending on what the user wants to build. Element types, however, are the
 * same for all open designs. Hence, type information is stored in a shared
 * <em>data dictionary</em>. Every concrete element type has a Java class
 * that implements the element.
 * <p>
 * Meta-data serves two key roles. First, it provides information that the core
 * implementation needs to correctly model the various elements. Second, it is
 * useful to the UI to provide information about elements. For example, the
 * property sheet can use the meta-data to determine the set of properties for
 * an element, the display names of each property, the data type, and any
 * special UI builders required.
 * 
 * <h3>Properties and Property Types</h3>
 * 
 * Most elements define properties. A property is simply something that the user
 * can set about the element such as its name, or size, or color. Property
 * information appears in three forms, which are easy to confuse.
 * <dl>
 * <dt><strong>Property type </strong></dt>
 * <dd>A description of the type of a property. Many properties can share the
 * same type. For example, foreground color and background color are both
 * properties of type color. Property types are defined by the implementation
 * team and are defined in the data dictionary.</dd>
 * 
 * <dt><strong>Property </strong></dt>
 * <dd>A property is the definition of an attribute of an element, and consists
 * of a name and a property type. Properties are of several kinds as described
 * below. The property is also a definition: all elements share the same set of