[webkit-help] When does ImageDecoder get destroyed

[n179911]

Hi,

Can you please tell me when does gdb) when does an ImageDecoder get destroyed?
I set breakpoints in the destructor of ImageDecoder, and I see it gets call in
1. Timer get fired?

#7  0x00b81d66 in WebCore::CachedImage::destroyDecodedData (this=0x880e800)
    at WebCore/loader/CachedImage.cpp:331
#8  0x00b80c63 in WebCore::CachedImage::decodedDataDeletionTimerFired (
    this=0x880e800) at WebCore/loader/CachedImage.cpp:79
#9  0x00b827b2 in WebCore::Timer<WebCore::CachedImage>::fired (this=0x880e994)

2. CachedImage destoryDecodedData?

#4  0x00b81de8 in WebCore::CachedImage::destroyDecodedData (this=0x88594c0)
    at WebCore/loader/CachedImage.cpp:335
#5  0x00b81916 in WebCore::CachedImage::clear (this=0x88594c0)
    at WebCore/loader/CachedImage.cpp:229
#6  0x00b81be3 in WebCore::CachedImage::error (this=0x88594c0)
    at WebCore/loader/CachedImage.cpp:307

So can you please tell me to understand
1. does each Image loaded has 1 ImageDecoder? So for a html page with
10 images, it has 10 ImageDecoder?
2. what is the Timer for case #1 for?
3. Why when I navigate to a new page, why the ImageDecoder destructer
(for the Images of the old page) never get called?

Thank you.