Ender Dragon will not spawn with Ender Crystals

Please attach the crash report ([minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt), otherwise we can not diagnose this issue.
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Issue is not Resolved, still can not respawn Ender Dragon. There is no crash report for this bug, no crashes for the last 7 months.