pgAdmin III commit: Fix crashes by limiting the size of explainPopup

Fix crashes by limiting the size of explainPopup

For very long queries, pgAdmin tries to create windows greater than
65536 pixels, which is not supported by X11 and therefor leads to
XErrors, which in turn cause pgadmin3 to close because of assertions.

Branch
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REL-1_14_0_PATCHES

Details
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http://git.postgresql.org/gitweb?p=pgadmin3.git;a=commitdiff;h=c60ecb0238c93ce85be791186e45506d99e4bb31
Author: Clemens Eisserer <linuxhippy@gmail.com>

Modified Files
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CHANGELOG                     |    2 ++
pgadmin/ctl/explainCanvas.cpp |    8 +++++++-
2 files changed, 9 insertions(+), 1 deletions(-)