[processing] Move some SVG icons out of plugin to themes

...and swap to using QgsApplication methods for retrieving cached icons,
implement svgIconPath for providers with SVG icons

Author: nyalldawson

images/images.qrc

@@ -550,6 +550,14 @@
         <file>themes/default/mTaskRunning.svg</file>
         <file>themes/default/mTaskTerminated.svg</file>
         <file>themes/default/mTaskCancel.svg</file>
+        <file>themes/default/providerGdal.svg</file>
+        <file>themes/default/providerGrass.svg</file>
+        <file>themes/default/providerQgis.svg</file>
+        <file>themes/default/providerR.svg</file>
+        <file>themes/default/providerTaudem.svg</file>
+        <file>themes/default/processingModel.svg</file>
+        <file>themes/default/processingScript.svg</file>
+        <file>themes/default/processingAlgorithm.svg</file>
     </qresource>
     <qresource prefix="/images/tips">
         <file alias="symbol_levels.png">qgis_tips/symbol_levels.png</file>

python/plugins/processing/images/alg.svg …s/themes/default/processingAlgorithm.svgpython/plugins/processing/images/alg.svg renamed to images/themes/default/processingAlgorithm.svg python/plugins/processing/images/alg.svg renamed to images/themes/default/processingAlgorithm.svg

@@ -72,13 +72,13 @@ def initGui(self):
         self.toolboxAction = self.toolbox.toggleViewAction()
         self.toolboxAction.setObjectName('toolboxAction')
         self.toolboxAction.setIcon(
-            QIcon(os.path.join(cmd_folder, 'images', 'alg.svg')))
+            QgsApplication.getThemeIcon("/processingAlgorithm.svg"))
         self.toolboxAction.setText(self.tr('&Toolbox'))
         self.iface.registerMainWindowAction(self.toolboxAction, 'Ctrl+Alt+T')
         self.menu.addAction(self.toolboxAction)
 
         self.modelerAction = QAction(
-            QIcon(os.path.join(cmd_folder, 'images', 'model.svg')),
+            QgsApplication.getThemeIcon("/processingModel.svg"),
             self.tr('Graphical &Modeler...'), self.iface.mainWindow())
         self.modelerAction.setObjectName('modelerAction')
         self.modelerAction.triggered.connect(self.openModeler)