Using Find it, assigning to the concern owner. Below are the find it results -- 

The result is a list of CLs that change the crashed files. 

Author: tsepez
Project: chromium-pdfium
Changelist: https://pdfium.googlesource.com/pdfium.git/+/833619b4441915c7c55085d44b3221eaef0d9800
Time: Wed Dec 07 09:21:17 2016 -0800
Lines 122-124, 131-132 of file fpdfview.cpp which potentially caused crash are changed in this cl (frame #6, "").
Minimum distance from crash line to modified line: 0. (file: fpdfview.cpp, crashed on: 131, modified: 131). 

Author: tsepez
Project: chromium-pdfium
Changelist: https://pdfium.googlesource.com/pdfium.git/+/bea049784abf7c32d0b9758fc77d0e601d5c232b
Time: Thu Dec 01 13:54:42 2016 -0800
Lines 120-141 of file fpdfview.cpp which potentially caused crash are changed in this cl (frame #6, "").
Minimum distance from crash line to modified line: 0. (file: fpdfview.cpp, crashed on: 128, modified: 128).

@tsepez -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

ClusterFuzz has detected this issue as fixed in range 440242:440280.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=6009488336486400

Fuzzer: tokenfuzz_pdf_curated
Job Type: linux_ubsan_chrome
Platform Id: linux

Crash Type: Float-cast-overflow
Crash Address: 
Crash State:
  FXSYS_round
  DrawAxialShading
  CPDF_RenderStatus::DrawShading
  
Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_ubsan_chrome&range=435261:438085
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_ubsan_chrome&range=440242:440280

Minimized Testcase (7.53 Kb): https://cluster-fuzz.appspot.com/download/AMIfv96A_YYaXciHzmrpNB75qQ6x2I1s0lGa1DA6HhvGsrwXwhSg_Y3lXiCYlH55salsJUiWVm78HEv5vdb0zwhkwiTXQu7AMZXbAkg3O4EW0LfUYAbd6bkCG__nyilQm5toMf3wS6umr4gnZtXttzLJH1jGpKLhHg?testcase_id=6009488336486400

See https://dev.chromium.org/Home/chromium-security/bugs/reproducing-clusterfuzz-bugs for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 6009488336486400 is verified as fixed, so closing issue.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.