Utils: Don't start at end of Markdown document

QTextEdit::show will try to scroll so that the cursor is visible.
By default the cursor is at the end of the document after
::setMarkdown().

To counteract we reset the cursor to the top.

Change-Id: I0e25878f32775de715fd4789d45274492b2981fe
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/libs/utils/markdownbrowser.cpp

@@ -413,6 +413,9 @@ void MarkdownBrowser::setMarkdown(const QString &markdown)
 {
     document()->setMarkdown(markdown);
     postProcessDocument(true);
+    // Reset cursor to start of the document, so that "show" does not
+    // scroll to the end of the document.
+    setTextCursor(QTextCursor(document()));
 }
 
 void MarkdownBrowser::postProcessDocument(bool firstTime) const