GitLab

Motivation: hide SkPDFDevice and SkPDFDocument behind PdfMetafileSkia class.

pdf_metafile_skia.cc:
    Implement GetVectorCanvasForNewPage.
    Remove StartPageForVectorCanvas.
    Own the SkCanvas pointer (current_page_canvas_).
    Replace page_outstanding_ field with a method that checks to see
    if current_page_canvas_ is NULL.
    Implement SaveTo.

skia::VectorPlatformDeviceSkia
    remove class

print_web_view_helper.cc
    Remove calls to canvas->getTopDevice()->setDrawingArea(...); (SkDFDevice)
    This API is no longer effective.

print_web_view_helper_linux.cc,
print_web_view_helper_mac.mm,
print_web_view_helper_pdf_win.cc:
    call GetVectorCanvasForNewPage rather than StartPageForVectorCanvas

BUG=278148

Review URL: https://codereview.chromium.org/704813002

Cr-Commit-Position: refs/heads/master@{#303522}