Style conflict issues in html blocks in Portfolio pages

[Steven]

TITLE: Style conflict issues in html blocks in Portfolio pages

BUG SUMMARY: There seems to be a conflict with inline styles in an html document and the portfolio page styling.
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Environment tested: Master
Browser tested: Chrome

PRECONDITIONS:
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1) HTML document exists (created by using ODT document and saving as html)
     a) Heading tags
     b) bullet list with nested items
     c) numbered list with nested items
     d) Paragraph text
     e) Image
     f) table
     g) embedded Excel spreadsheet:

TEST STEPS:
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1) Log in as mahara user
2) create a portfolio page with a 3 column layout (default)
3) add an html block using the html file mentioned in preconditions

Expected Result: The html should respect the portfolio page layout - so if a table is larger than the column, then scroll bars should be used. The Portfolio page should also respect the HTML file (if the file has bullet and numbered lists, they should be displayed correctly

Actual Result: The portfolio page is displaying lists and tables incorrectly - see screenshot attached