StandalonePluginHolder:  Fix out-of-bounds read when audio callbacks use larger-than-expected buffers

Projucer:  Fixed a potential crash in JucerTreeViewBase when dereferencing a deleted pointer to the underlying TreeViewItem

When passing in valid data with zero size, replaceWith() will do nothing and leave the MemoryBlock in its previous state which may be unexpected. replaceAll() will reset the MemoryBlock and resize it to 0

The plugin should interpret the arguments as VstSpeakerArrangement**
instances. It should modify the pointed-to VstSpeakerArrangement* so
that it points to a long-lived VstSpeakerArrangement in the plugin.

Audition incorrectly increments the ref-count of the IPlugView* returned from IEditController::createView() and never fully releases it. This commit reverts e0306d25 for Audition to ensure that an editor is always returned, otherwise Audition displays a blank GUI.

TextEditor:  Use caret position relative to the Component top-left when calculating scroll amounts in scrollEditorToPositionCaret() and scrollToMakeSureCursorIsVisible()

This fixes a regression introduced by
6e9261ea which meant that components
were not given a chance to respond to shortcut keypresses if those same
keypresses were registered for a menu item. This resulted in behaviour
where shortcuts such as 'cmd+c' would not be passed to a focused
TextEditor if a different command with the same shortcut was registered
in the main menu.

With this change in place, we now check whether the menu item's shortcut
keys match the current event's pressed keys. If the keypresses match, we
can assume that the event was triggered by the keyboard, and dispatch
the keypresses to the ComponentPeer. If the keypresses do not match,
then the menu item was likely selected using space/return, or by
clicking, in which case the event is dispatched directly to the
ApplicationCommandManager.