Adds some handlers and project creation state toggles in ProjectOperations

[netonjm]

Adds some handlers and project creation state toggles in ProjectOperations

Fixes VSTS #984930 - Get to code can be re-entered during new project flow

Requires https://github.com/xamarin/md-addins/pull/6161

[netonjm]

rebased!

[sevoku]

@monojenkins rebase

[sevoku]

@mrward any idea how this change might cause the NuGet test failure?

1) Error : Microsoft.VSForMac.Tests.SimpleNuGetTests.TestAddAndUpdatePackages
System.TimeoutException : Timeout while executing WaitForElement: c => c.Window ().Marked ("Manage NuGet Packages");

[mrward]

Should have no affect on NuGet. Looking at the test report the screenshots have some error about being unable to load Xamarin.Ide.

[mrward]

Xamarin.Ide is being loaded. The problem seems to be a null ref in Get to code looking at the IDE log in the failing test.

ERROR[2020-01-22 22:51:37Z]: Add-in error (MonoDevelop.Xamarin.Ide,8.6): Error while getting object for node in path '/MonoDevelop.Ide/TypeExtensions/MonoDevelop.Ide.WelcomePage.IWelcomeWindowProvider'.
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object
  at Xamarin.Ide.GetToCode.GetToCodeDialog.RefreshViewEnableStates () [0x00000] in /Users/runner/runners/2.164.3/work/1/s/md-addins/Xamarin.Ide/Xamarin.Ide/Xamarin.Ide.GetToCode/GetToCodeDialog.cs:275 
  at Xamarin.Ide.GetToCode.GetToCodeDialog.Initialize () [0x00360] in /Users/runner/runners/2.164.3/work/1/s/md-addins/Xamarin.Ide/Xamarin.Ide/Xamarin.Ide.GetToCode/GetToCodeDialog.cs:359 
  at Xamarin.Ide.GetToCode.GetToCodeDialog..ctor () [0x00011] in /Users/runner/runners/2.164.3/work/1/s/md-addins/Xamarin.Ide/Xamarin.Ide/Xamarin.Ide.GetToCode/GetToCodeDialog.cs:237 
  at Xamarin.Ide.GetToCode.GetToCodeWindowProvider..ctor () [0x00034] in /Users/runner/runners/2.164.3/work/1/s/md-addins/Xamarin.Ide/Xamarin.Ide/Xamarin.Ide.GetToCode/GetToCodeDialog.cs:102 
  at (wrapper managed-to-native) System.Reflection.RuntimeConstructorInfo.InternalInvoke(System.Reflection.RuntimeConstructorInfo,object,object[],System.Exception&)
  at System.Reflection.RuntimeConstructorInfo.InternalInvoke (System.Object obj, System.Object[] parameters, System.Boolean wrapExceptions) [0x00005] in /Users/builder/jenkins/workspace/build-package-osx-mono/2019-10/external/bockbuild/builds/mono-x64/mcs/class/corlib/System.Reflection/RuntimeMethodInfo.cs:936 

That RefreshViewEnableStates method is new I think.

[sevoku]

ooh! @mrward thanks!

[netonjm]

good catch! thanks!