Fix typo in tools/metrics/histograms/enums.xml

Bug: 1136942
Change-Id: Ia21e9ad0b35fb9e552137606801750fab35d6c65
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2532560Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Commit-Queue: Elad Alon <eladalon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826528}

tools/metrics/histograms/enums.xml

@@ -64229,7 +64229,7 @@ https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_2.7.1.pdf
   <int value="6" label="CanvasCaptureStream"/>
   <int value="7" label="VideoCaptureStream"/>
   <int value="8" label="GetDisplayMedia"/>
-  <int value="9" label="kGetCurrentBrowsingContextMedia"/>
+  <int value="9" label="GetCurrentBrowsingContextMedia"/>
 </enum>
 
 <enum name="RTCQuicStreamReadIntoResult">