🔪 layoutStyles call in drawFramework step

- this appear to be no longer needed
- adapt plot_api test to relied on layoutStyles spy counts

Author: etpinard

src/plot_api/plot_api.js

@@ -245,9 +245,7 @@ exports.plot = function(gd, data, layout, config) {
                 .attr('height', fullLayout.height);
         }
 
-        return Lib.syncOrAsync([
-            subroutines.layoutStyles
-        ], gd);
+        return Plots.previousPromises(gd);
     }
 
     // draw anything that can affect margins.

test/jasmine/tests/plot_api_test.js

@@ -2440,9 +2440,7 @@ describe('Test plot api', function() {
 
         function countCalls(counts) {
             var callsFinal = Lib.extendFlat({}, counts);
-            // TODO: do we really need to do layoutStyles twice in Plotly.plot?
-            // We get one from drawFramework and another directly from Plotly.plot.
-            callsFinal.layoutStyles = (counts.layoutStyles || 0) + 2 * (counts.plot || 0);
+            callsFinal.layoutStyles = (counts.layoutStyles || 0) + (counts.plot || 0);
 
             mockedMethods.forEach(function(m) {
                 expect(subroutines[m]).toHaveBeenCalledTimes(callsFinal[m] || 0);