CXFA_TextParseContext::m_eDisplay is too small
CXFA_TextParseContext::m_eDisplay is too small

enum FDE_CSSDISPLAY contains about 20 values, which won't fit into
4 bits.  Avoid packing and burn the memory, since I worry about the
m_dwMatchedDelcs geting truncated, too.

R=dsinclair@chromium.org

Review URL: https://codereview.chromium.org/1771193002 .

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