When failing to hot reload in some cases, the compile button in the editor will disappear and Hot Reloads will stop occurring. This tends to happen randomly in other scenarios but the method above is the only one that has been a 100% reproduction case thus far. Presumably, this reproduction case will work when trying to add any class that is set to Minimal API or that would cause the Hot Reload to fail upon being added

Regression?: NO
This occurred in 4.10.4 & 4.11.2

Steps to Reproduce
  1. Create a new C++ project
  2. Select File > New C++ Class... > Show All Classes > PointLight > Next > Create Class
  3. The compilation will fail; Press Yes on the window asking if you wish to view the Output Log
    Result: The Compile button disappears and further Hot Reloads do not occur
    Expected: The initial hot reload should fail, but the compile button shouldn't disappear and subsequent hot reloads should occur

Additional Repro reported by user:

  1. Create a new C++ project
  2. Select File > New C++ Class... > Actor > Next > Create Class
  3. Add the following code to the .h file (declaring a Blueprint Callable function):
    UFUNCTION(BlueprintCallable, Category = "MyFunction")
    	void MyFunction();
  4. Compile through Visual Studio
  5. Once the compile fails due to the function that we declared not being defined, return to the editor
    Result: The compile button has disappeared
    Expected: The compile button should still be there although the hot reload failed.

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ComponentUE - Foundation - Core
Affects Versions4.
Target Fix4.13
Fix Commit3087139
Main Commit3050320
Release Commit3087139
CreatedJun 2, 2016
ResolvedAug 12, 2016
UpdatedApr 27, 2018
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