glamor: Fix xRGB->ARGB composite in certain cases

In some cases, glamor will decide to convert a pixmap into one of
a different size to supplant the one incoming to glamor_composite.
For out of bounds calculations for RepeatNone, we still need to use
the original pixmap for the bounds calculations. This patch
will detect this case and then use the original pixmap dimensions
for out of bounds calculations.

Any pixmap dimension of 0 will force a negative
texture co-ordinate value. All samples will be deemed out of
bounds by the fragment shader (transparent for RepeatNone).
This lines up with the behavior of fbComposite and the XRender spec.

Signed-off By: Isaac Bosompem <mrisaacb@google.com>
9 jobs for glamorcomposite in 4 minutes and 31 seconds (queued for 11 seconds)
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  Docker Image
passed debian-buster #12909716

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  Build And Test
passed autotools #12920684

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passed meson #12920685

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passed meson-noglamor #12920686

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passed mingw-cross-build #12920687

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failed autotools #12909717

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failed meson #12909718

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failed meson-noglamor #12909719

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failed mingw-cross-build #12909720

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