Bitmap not released when targetSdkVersion is 19

I'm developing a Android app which use Radaee to view PDF Files.
When I check the newest sample PDFViewer3.6.2b_Android Studio.zip, I found it can't work fine when I change RDPDFReader module's build.gradle like this:

targetSdkVersion 19

The Problem is when I go to [ViewPager] from the Main page , and scroll to next page, next page, the memory is keep increasing, until crash .
The memory is properly released before I changed the targetSdkVersion.

targetSdkVersion 8

Is this a bug? Or I used it wrong?

Hi,
we have sent the issue to our developers.
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Hi,
we have created a new ticket for you with the fix.
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