BreakingContext and RenderText::computePreferredLogicalWidths() pre-calculates space width and if the associated font does not have space glyph we initiate a fallback font even if the text does not need it. Since both the primary and the fallback fonts are used to figure out ascent/descent information for lines, if the fallback fonts' ascent/descent values are bigger, the line gets misplaced. (as opposed to where it would be placed, if the primary font had space glyph)
Created attachment 252882 [details] Patch
Comment on attachment 252882 [details] Patch Attachment 252882 [details] did not pass mac-ews (mac): Output: http://webkit-queues.appspot.com/results/5717670238355456 New failing tests: fast/ruby/ruby-expansion-cjk-3.html fast/ruby/ruby-expansion-cjk.html fast/ruby/ruby-expansion-cjk-5.html platform/mac/svg/fonts/svg-font-general.html fast/ruby/ruby-expansion-cjk-2.html fast/ruby/ruby-expansion-cjk-4.html
Created attachment 252884 [details] Archive of layout-test-results from ews100 for mac-mavericks The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews100 Port: mac-mavericks Platform: Mac OS X 10.9.5
Comment on attachment 252882 [details] Patch Attachment 252882 [details] did not pass mac-wk2-ews (mac-wk2): Output: http://webkit-queues.appspot.com/results/4591770331512832 New failing tests: fast/ruby/ruby-expansion-cjk-3.html fast/ruby/ruby-expansion-cjk.html fast/ruby/ruby-expansion-cjk-5.html platform/mac/svg/fonts/svg-font-general.html fast/ruby/ruby-expansion-cjk-2.html fast/ruby/ruby-expansion-cjk-4.html
Created attachment 252885 [details] Archive of layout-test-results from ews106 for mac-mavericks-wk2 The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews. Bot: ews106 Port: mac-mavericks-wk2 Platform: Mac OS X 10.9.5
Comment on attachment 252882 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=252882&action=review > Source/WebCore/rendering/line/BreakingContext.h:86 > + enum WordTrailingSpaceState { Uninitialized, Computed }; enum class
Created attachment 252902 [details] Patch
(In reply to comment #5) > Created attachment 252885 [details] > Archive of layout-test-results from ews106 for mac-mavericks-wk2 > > The attached test failures were seen while running run-webkit-tests on the > mac-wk2-ews. > Bot: ews106 Port: mac-mavericks-wk2 Platform: Mac OS X 10.9.5 Progressions.
Created attachment 252919 [details] Patch
Comment on attachment 252919 [details] Patch Clearing flags on attachment: 252919 Committed r184150: <http://trac.webkit.org/changeset/184150>
All reviewed patches have been landed. Closing bug.