Common: remove hwnd_data_cache (#1223)

The cache was introduced to improve performance by not querying the
OS for the window process path every time we need to check if the window
is interesting to FancyZones. Since then other changes were made to the
the way we check the windows. Right now, the IsInterestingWindow function is
called when:

  1) WinKey + arrows are used
  2) window is started to be dragged
  3) window is created

1) and 2) are initiated by the user, happen only once per interaction so
their performance impact can be dismissed. The 3) happens all the time
but for the most part the check for WS_CHILD or
GetAncestor(window, GA_ROOT) == window will filter those out. In the
end, only top-level windows will be queried for their path.

Removing the cache improves code readability and will make code
maintenance easier.

src/common/common.vcxproj

@@ -102,7 +102,6 @@
     <ClInclude Include="notifications.h" />
     <ClInclude Include="window_helpers.h" />
     <ClInclude Include="icon_helpers.h" />
-    <ClInclude Include="hwnd_data_cache.h" />
     <ClInclude Include="json.h" />
     <ClInclude Include="monitors.h" />
     <ClInclude Include="on_thread_executor.h" />
@@ -125,7 +124,6 @@
     <ClCompile Include="d2d_text.cpp" />
     <ClCompile Include="d2d_window.cpp" />
     <ClCompile Include="dpi_aware.cpp" />
-    <ClCompile Include="hwnd_data_cache.cpp" />
     <ClCompile Include="json.cpp" />
     <ClCompile Include="monitors.cpp" />
     <ClCompile Include="notifications.cpp" />