PDF Page Rotation Performance and Functionality Issues

[gokulreizend]

Problem Summary
PDF page rotation feature is extremely slow (13+ seconds).

Current Behavior
Rotation takes 13-32 seconds for a 4MB PDF with 25 pages
Memory usage spikes during rotation
UI freezes during the operation

[espresso3389]

To rotate PDF pages (on GUI), all you have to do is this:

doc.pages = [
  doc.pages[0],          // Page 2 with original rotation
  doc.pages[1],          // Page 2 with original rotation
  doc.pages[2].rotatedCW90(), // Page 3 rotated right
  ...
];

And, it does not take so much time.