Doc: Add section about perf profiler statistics view

Change-Id: I5d4a640f42f81f7c81b8c3f3b7f8bc06dff62671
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@theqtcompany.com>

doc/src/analyze/cpu-usage-analyzer.qdoc

@@ -267,6 +267,36 @@
     overall bottleneck, and the thread with less samples taken has likely spent
     time waiting for external events such as I/O or a mutex.
 
+    \section1 Viewing Statistics
+
+    The \uicontrol Statistics view displays the number of samples each function
+    in the timeline was contained in, in total and when on the top of the
+    stack (called \c self). This allows you to examine which functions you need
+    to optimize. A high number of occurrences might indicate that a function is
+    triggered unnecessarily or takes very long to execute.
+
+    Click on a row to move to the respective function in the source code in the
+    code editor.
+
+    The \uicontrol Callers and \uicontrol Callees panes show dependencies
+    between functions. They allow you to examine the internal functions of the
+    application. The \uicontrol Callers pane summarizes the functions that
+    called the function selected in the main view.  The \uicontrol Callees pane
+    summarizes the functions called from the function selected in the main
+    view.
+
+    Click on a row to move to the respective function in the source code in the
+    code editor and select it in the main view.
+
+    When you select a stack frame in the \uicontrol Timeline view, information
+    about it is displayed in the \uicontrol Statistics view. To view a time
+    range in the \uicontrol Statistics view, select
+    \uicontrol {Limit Statistics to Selected Range} in the context menu in the
+    \uicontrol Timeline view.
+
+    To copy the contents of one view or row to the clipboard, select
+    \uicontrol {Copy Table} or \uicontrol {Copy Row} in the context menu.
+
     \section1 Loading Perf Data Files
 
     You can load any \c perf.data files generated by recent versions of the