RFR: JDK-8293480: IGV: Update Bytecode and ControlFlow Component immediately when opening a new graph

[Tobias Holenstein]

The `BytecodeViewTopComponent` and `ControlFlowTopComponent` represent information depending on what graph is open in `EditorTopComponent`. Previously, `BytecodeViewTopComponent` and `ControlFlowTopComponent` did not update its content immediately when a new graph from a different group is opened in `EditorTopComponent`. They also did not update when switching between two tabs of open graph. 

We missed to `fire()` a `diagramChangedEvent` in the constructor of `EditorTopComponent`. We also need to fire when `BytecodeViewTopComponent` and `ControlFlowTopComponent` are initially opened. 
<img width="1291" alt="Update" src="https://user-images.githubusercontent.com/71546117/188860123-825a67fd-aab3-4500-8a47-8fa56eb9aeed.png">

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Commit messages:
 - Updated Bytecode and ControlFlow Component immediately when opening a new graph

Changes: https://git.openjdk.org/jdk/pull/10196/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10196&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293480
  Stats: 53 lines in 4 files changed: 13 ins; 8 del; 32 mod
  Patch: https://git.openjdk.org/jdk/pull/10196.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10196/head:pull/10196

PR: https://git.openjdk.org/jdk/pull/10196