commit f2291c41ff45ff3108ef05539fadf7fafac2e7cd Author: Arthur Edelstein arthuredelstein@gmail.com Date: Tue Jun 21 14:31:45 2016 -0700

squash! Bug 1517: Reduce precision of time for Javascript.

Bug 19478: Prevent File API from leaking ms-resolution current time --- dom/base/File.cpp | 3 ++- dom/base/MultipartBlobImpl.cpp | 4 +++- 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/dom/base/File.cpp b/dom/base/File.cpp index 5cc20a7..694f8fb 100644 --- a/dom/base/File.cpp +++ b/dom/base/File.cpp @@ -750,7 +750,8 @@ BlobImplBase::GetLastModified(ErrorResult& aRv) { NS_ASSERTION(mIsFile, "Should only be called on files"); if (IsDateUnknown()) { - mLastModificationDate = PR_Now(); + // Round to nearest 100 ms. + mLastModificationDate = floor(PR_Now() / 100000) * 100000; }

return mLastModificationDate / PR_USEC_PER_MSEC; diff --git a/dom/base/MultipartBlobImpl.cpp b/dom/base/MultipartBlobImpl.cpp index 9867142..b1e088a 100644 --- a/dom/base/MultipartBlobImpl.cpp +++ b/dom/base/MultipartBlobImpl.cpp @@ -273,7 +273,9 @@ MultipartBlobImpl::SetLengthAndModifiedDate(ErrorResult& aRv) // x.getTime() < f.dateModified.getTime() // could fail. mLastModificationDate = - lastModifiedSet ? lastModified * PR_USEC_PER_MSEC : JS_Now(); + lastModifiedSet ? lastModified * PR_USEC_PER_MSEC + // Round to nearest 100 ms + : floor(JS_Now() / 100000) * 100000; } }