Support Series derived from a different dataframe as row_sel.

[ueshin]

No description provided.

[codecov-io]

Codecov Report

Merging #1155 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1155      +/-   ##
==========================================
+ Coverage   95.22%   95.23%   +<.01%     
==========================================
  Files          35       35              
  Lines        7063     7065       +2     
==========================================
+ Hits         6726     6728       +2     
  Misses        337      337

Impacted Files	Coverage Δ
databricks/koalas/series.py	96.46% <100%> (-0.03%)	⬇️
databricks/koalas/indexing.py	94.38% <100%> (+0.16%)	⬆️

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