mozilla-central: changeset 247997:b4f355ca322fb6ca04d795720209dd59addc8a14

author	dominique vincent <domivinc@toitl.com>
	Fri, 05 Jun 2015 16:25:16 +0200
changeset 247997	b4f355ca322fb6ca04d795720209dd59addc8a14
parent 247996	b971fbbbe37e14d786e036758a1302eacadce226
child 247998	4bd79939fea127dab2f1fbc64236d2a0dd8592fd
push id	28887
push user	kwierso@gmail.com
push date	Thu, 11 Jun 2015 01:10:53 +0000
treeherder	mozilla-central@1fd19d8fc936 [default view] [failures only]
perfherder	[talos] [build metrics] [platform microbench] (compared to previous push)
reviewers	kats
bugs	1171731
milestone	41.0a1
first release with	nightly linux32 bfd82015df48 / 41.0a1 / 20150611030208 / files nightly linux64 bfd82015df48 / 41.0a1 / 20150611030208 / files nightly mac bfd82015df48 / 41.0a1 / 20150611030208 / files nightly win32 bfd82015df48 / 41.0a1 / 20150611030208 / files nightly win64 bfd82015df48 / 41.0a1 / 20150611030208 / files
last release without	nightly linux32 5787d784485e / 41.0a1 / 20150610030209 / files nightly linux64 5787d784485e / 41.0a1 / 20150610030209 / files nightly mac 5787d784485e / 41.0a1 / 20150610030209 / files nightly win32 5787d784485e / 41.0a1 / 20150610030209 / files nightly win64 5787d784485e / 41.0a1 / 20150610030209 / files

--- a/layout/base/PositionedEventTargeting.cpp
+++ b/layout/base/PositionedEventTargeting.cpp
@@ -412,17 +412,18 @@ IsElementClickableAndReadable(nsIFrame* 
   if ((pc->AppUnitsToGfxUnits(frameSize.height) * cumulativeResolution) < limitReadableSize ||
       (pc->AppUnitsToGfxUnits(frameSize.width) * cumulativeResolution) < limitReadableSize) {
     return false;
   }
   nsRefPtr<nsFontMetrics> fm;
   nsLayoutUtils::GetFontMetricsForFrame(aFrame, getter_AddRefs(fm),
     nsLayoutUtils::FontSizeInflationFor(aFrame));
   if (fm) {
-    if ((pc->AppUnitsToGfxUnits(fm->EmHeight()) * cumulativeResolution) < limitReadableSize) {
+    if ((fm->EmHeight() > 0) && // See bug 1171731
+        (pc->AppUnitsToGfxUnits(fm->EmHeight()) * cumulativeResolution) < limitReadableSize) {
       return false;
     }
   }
 
   return true;
 }
 
 nsIFrame*