Debugger: Add infrastructure for message tracepoints.

Add context menu to add a 'message tracepoint', that is,
a trace point that outputs a user message and continues.
Intended to be a replacement for manually inserting
a qDebug() into the code to understand the call sequence.
Yet to be implemented for gdb.

Change-Id: I1c303001421fbbae74d98d15d52718579350db6e
Rubber-stamped-by: hjk
Reviewed-on: http://codereview.qt.nokia.com/756
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

src/plugins/debugger/breakpoint.h

@@ -182,11 +182,12 @@ enum BreakpointParts
     TypePart = 0x400,
     PathUsagePart = 0x800,
     CommandPart = 0x1000,
+    MessagePart = 0x2000,
 
     AllParts = FileAndLinePart|FunctionPart
                |ExpressionPart|AddressPart|ConditionPart
                |IgnoreCountPart|ThreadSpecPart|ModulePart|TracePointPart
-               |EnabledPart|TypePart|PathUsagePart|CommandPart
+               |EnabledPart|TypePart|PathUsagePart|CommandPart|MessagePart
 };
 
 inline void operator|=(BreakpointParts &p, BreakpointParts r)
@@ -229,6 +230,7 @@ public:
     QString functionName;
     QString module;          //!< module for file name
     QString command;         //!< command to execute
+    QString message;         //!< message
     bool tracepoint;
 };