adapt polar to new per trace/item _extremes

- N.B. polar is the only subplot apart from cartesian that
  used Axes.expand and friends.

Author: etpinard

src/plots/polar/layout_defaults.js

@@ -80,11 +80,11 @@ function handleDefaults(contIn, contOut, coerce, opts) {
         // Furthermore, angular axes don't have a set range.
         //
         // Mocked domains and ranges are set by the polar subplot instances,
-        // but Axes.expand uses the sign of _m to determine which padding value
+        // but Axes.findExtremes uses the sign of _m to determine which padding value
         // to use.
         //
-        // By setting, _m to 1 here, we make Axes.expand think that range[1] > range[0],
-        // and vice-versa for `autorange: 'reversed'` below.
+        // By setting, _m to 1 here, we make Axes.findExtremes think that
+        // range[1] > range[0], and vice-versa for `autorange: 'reversed'` below.
         axOut._m = 1;
 
         switch(axName) {

src/plots/polar/polar.js

@@ -300,9 +300,10 @@ proto.updateLayout = function(fullLayout, polarLayout) {
 proto.doAutoRange = function(fullLayout, polarLayout) {
     var radialLayout = polarLayout.radialaxis;
     var ax = this.radialAxis;
+    ax._subplot = this.id;
 
     setScale(ax, radialLayout, fullLayout);
-    doAutoRange(ax);
+    doAutoRange(this.gd, ax);
 
     radialLayout.range = ax.range.slice();
     radialLayout._input.range = ax.range.slice();
@@ -1207,12 +1208,6 @@ proto.fillViewInitialKey = function(key, val) {
 
 function setScale(ax, axLayout, fullLayout) {
     Axes.setConvert(ax, fullLayout);
-
-    // _min and _max are filled in during Axes.expand
-    // and cleared during Axes.setConvert
-    ax._min = axLayout._min;
-    ax._max = axLayout._max;
-
     ax.setScale();
 }
 

src/traces/scatterpolar/calc.js

@@ -48,7 +48,7 @@ module.exports = function calc(gd, trace) {
     }
 
     var ppad = calcMarkerSize(trace, len);
-    Axes.expand(radialAxis, rArray, {ppad: ppad});
+    trace._extremes.radialaxis = Axes.findExtremes(radialAxis, rArray, {ppad: ppad});
 
     calcColorscale(trace);
     arraysToCalcdata(cd, trace);

src/traces/scatterpolargl/index.js

@@ -36,13 +36,7 @@ function calc(container, trace) {
     stash.r = rArray;
     stash.theta = thetaArray;
 
-    Axes.expand(radialAxis, rArray, {tozero: true});
-
-    if(angularAxis.type !== 'linear') {
-        angularAxis.autorange = true;
-        Axes.expand(angularAxis, thetaArray);
-        delete angularAxis.autorange;
-    }
+    trace._extremes.radialaxis = Axes.findExtremes(radialAxis, rArray, {tozero: true});
 
     return [{x: false, y: false, t: stash, trace: trace}];
 }