Remove the last windowing function and make the metric work in chromium.

Now tested with chromium's trace_processor_shell:

tools/perf/core/tbmv3/run_tbmv3_metric.py \
--trace ~/chromium-team/pixel4_220120_7_flings \
--metric janky_time_per_scroll_processing_time \
--trace-processor-path out/linux-release-tmp/trace_processor_shell

Bug: internal b/150600174
Change-Id: Ib1015fe876f60858b138838a1a34195a8f6e0884
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2095098Reviewed-by: Stephen Nusko <nuskos@chromium.org>
Reviewed-by: Mikhail Khokhlov <khokhlov@google.com>
Commit-Queue: Stephen Nusko <nuskos@chromium.org>
Auto-Submit: Stephen Nusko <nuskos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#748296}

tools/perf/core/tbmv3/metrics/janky_time_per_scroll_processing_time.sql

@@ -168,11 +168,11 @@ DROP TABLE IF EXISTS ScrollJanksMaybeNull;
 
 CREATE TABLE ScrollJanksMaybeNull AS
   SELECT
-    ROW_NUMBER() OVER (ORDER BY currScrollTs ASC) AS rowNumber,
     currBeginId,
     currUpdateDur,
     currScrollDur,
     currScrollId,
+    currScrollTs,
     CASE WHEN currBeginId != prevBeginId
     THEN
       0 ELSE
@@ -204,6 +204,22 @@ CREATE TABLE ScrollJanksMaybeNull AS
    GestureScrollUpdatesRowNumbers next ON currprev.currRowNumber + 1 = next.rowNumber
 ORDER BY currprev.currScrollTs ASC;
 
+-- TODO(nuskos): Once chromium TBMv3 supports windowing functions use
+-- ROW_NUMBER(ORDER BY ts ASC) OVER() instead.
+
+DROP TABLE IF EXISTS ScrollJanksMaybeNullRowNumbers;
+
+CREATE TABLE ScrollJanksMaybeNullRowNumbers AS
+SELECT
+  (SELECT COUNT(*)
+    FROM ScrollJanksMaybeNull prev
+    WHERE prev.currScrollTs < next.currScrollTs) + 1 as rowNumber,
+  *
+FROM
+  ScrollJanksMaybeNull next;
+
+
+
 -- This just lists outs the rowNumber (which is ordered by timestamp), its jank
 -- status and information about the update and scroll overall. Basically
 -- getting it into a next queriable format.
@@ -219,7 +235,7 @@ CREATE TABLE ScrollJanks AS
     (nextJank IS NOT NULL AND nextJank) OR
     (prevJank IS NOT NULL AND prevJank)
     AS jank
-  FROM ScrollJanksMaybeNull;
+  FROM ScrollJanksMaybeNullRowNumbers;
 
 -- Compute the total amount of nanoseconds from Janky GestureScrollUpdates and
 -- the total amount of nanoseconds we spent scrolling in the trace. Also need