PDFBOX-2214: graphics stack must have at least one element because of peek() in PDFStreamEngine

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1612363 13f79535-47bb-0310-9956-ffa450edef68
PDFBOX-2214: graphics stack must have at least one element because of peek() in PDFStreamEngine

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1612365 13f79535-47bb-0310-9956-ffa450edef68
PDFBOX-2214: revert last commit, didn't work

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1612368 13f79535-47bb-0310-9956-ffa450edef68