[M60 cherry pick] Initialize rects in SkValidatingReadBuffer readRect & readIRect on failure

TBR=reed@google.com

No-Tree-Checks: true
No-Try: true
No-Presubmit: true
Bug: 726199
Change-Id: Ibaf5391d01565a522d3230cd6ac066cc522ad739
Reviewed-on: https://skia-review.googlesource.com/18226
Reviewed-by: Robert Phillips <robertphillips@google.com>
1 file changed