✨ Support multiple running instance for inspectors (#6772)

Resolves #6189.


https://github.com/flutter/flutter-intellij/assets/15884415/b5a3438b-4fbd-4fa8-9027-fd3fe0f11963

## Implementation details

- `Browser` is a singleton in the previous implementation. The PR
updates it to be stored as a mapping between the tab name (the unique
device name) and the browser instance.
- `Content`s are also cached to ensure they can be added after removing
the empty content.

## Additional context

`FlutterPerformanceView` should be able to apply the same update but I
didn't investigate it yet.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] All existing and new tests are passing.

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Author: AlexV525

flutter-idea/src/io/flutter/jxbrowser/EmbeddedBrowser.java

@@ -37,6 +37,8 @@
 
 import java.awt.*;
 import java.io.File;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -50,7 +52,8 @@ public static EmbeddedBrowser getInstance(@NotNull Project project) {
     return Objects.requireNonNull(project.getService(EmbeddedBrowser.class));
   }
 
-  private Browser browser;
+  private final Map<@NotNull String, @NotNull Browser> browsers = new HashMap<>();
+  private final Map<@NotNull String, @NotNull Content> contents = new HashMap<>();
   private CompletableFuture<DevToolsUrl> devToolsUrlFuture;
 
   private EmbeddedBrowser(Project project) {
@@ -61,18 +64,46 @@ private EmbeddedBrowser(Project project) {
       System.setProperty("jxbrowser.logging.level", "ALL");
     }
 
+    ProjectManager.getInstance().addProjectManagerListener(project, new ProjectManagerListener() {
+      @Override
+      public void projectClosing(@NotNull Project project) {
+        for (final String key: browsers.keySet()) {
+          final Browser browser = browsers.get(key);
+          if (browser != null) {
+            try {
+              browser.close();
+            } catch (Exception ex) {
+              LOG.info(ex);
+            }
+            browsers.remove(key);
+          }
+        }
+        contents.clear();
+      }
+    });
+  }
+
+  private void openBrowserInstanceFor(String tabName) {
     try {
       final Engine engine = EmbeddedBrowserEngine.getInstance().getEngine();
       if (engine == null) {
         return;
       }
-
-      this.browser = engine.newBrowser();
-      browser.settings().enableTransparentBackground();
-      browser.on(ConsoleMessageReceived.class, event -> {
+      final Browser newBrowser = engine.newBrowser();
+      newBrowser.settings().enableTransparentBackground();
+      newBrowser.on(ConsoleMessageReceived.class, event -> {
         final ConsoleMessage consoleMessage = event.consoleMessage();
         LOG.info("Browser message(" + consoleMessage.level().name() + "): " + consoleMessage.message());
       });
+      final Browser oldBrowser = browsers.get(tabName);
+      if (oldBrowser != null) {
+        try {
+          oldBrowser.close();
+        } catch (Exception ex) {
+          LOG.info(ex);
+        }
+      }
+      browsers.put(tabName, newBrowser);
     }
     catch (UnsupportedRenderingModeException ex) {
       // Skip using a transparent background if an exception is thrown.
@@ -81,22 +112,7 @@ private EmbeddedBrowser(Project project) {
       LOG.info(ex);
       FlutterInitializer.getAnalytics().sendExpectedException("jxbrowser-setup", ex);
     }
-
     resetUrl();
-
-    ProjectManager.getInstance().addProjectManagerListener(project, new ProjectManagerListener() {
-      @Override
-      public void projectClosing(@NotNull Project project) {
-        if (browser != null) {
-          try {
-            browser.close();
-          } catch (Exception ex) {
-            LOG.info(ex);
-          }
-          browser = null;
-        }
-      }
-    });
   }
 
   /**
@@ -109,8 +125,13 @@ public void resetUrl() {
     this.devToolsUrlFuture = new CompletableFuture<>();
   }
 
-  public void openPanel(ContentManager contentManager, String tabName, DevToolsUrl devToolsUrl, Runnable onBrowserUnavailable) {
+  public void openPanel(ContentManager contentManager, @NotNull String tabName, DevToolsUrl devToolsUrl, Runnable onBrowserUnavailable) {
+    final Browser firstBrowser = browsers.get(tabName);
+    if (browsers.get(tabName) == null) {
+      openBrowserInstanceFor(tabName);
+    }
     // If the browser failed to start during setup, run unavailable callback.
+    final Browser browser = browsers.get(tabName);
     if (browser == null) {
       onBrowserUnavailable.run();
       return;
@@ -141,6 +162,17 @@ public void openPanel(ContentManager contentManager, String tabName, DevToolsUrl
         }
 
         contentManager.removeAllContents(false);
+        if (contents.get(tabName) != null) {
+          contents.remove(tabName);
+        }
+        for (final Content content: contents.values()) {
+          contentManager.addContent(content);
+        }
+        final Content previousContent = contents.get(tabName);
+        if (previousContent != null) {
+          contentManager.setSelectedContent(previousContent, true);
+          return;
+        }
         final Content content = contentManager.getFactory().createContent(null, tabName, false);
 
         // Creating Swing component for rendering web content
@@ -158,6 +190,8 @@ public void openPanel(ContentManager contentManager, String tabName, DevToolsUrl
           // TODO(helin24): Use differentiated icons for each tab and copy from devtools toolbar.
           content.setIcon(FlutterIcons.Phone);
           contentManager.addContent(content);
+          contentManager.setSelectedContent(content, true);
+          contents.put(tabName, content);
 
           // This is for pulling up Chrome inspector for debugging purposes.
           browser.set(PressKeyCallback.class, params -> {
@@ -227,7 +261,9 @@ private void updateUrlAndReload(Function<DevToolsUrl, DevToolsUrl> newDevToolsUr
         // Reload is no longer needed - either URL has been reset or there has been no change.
         return;
       }
-      browser.navigation().loadUrl(devToolsUrl.getUrlString());
+      for (final Browser browser: browsers.values()) {
+        browser.navigation().loadUrl(devToolsUrl.getUrlString());
+      }
     });
   }
 }

flutter-idea/src/io/flutter/run/FlutterDevice.java

@@ -111,6 +111,7 @@ public String toString() {
   /**
    * Given a collection of devices, return a unique name for this device.
    */
+  @NotNull
   public String getUniqueName(Collection<FlutterDevice> devices) {
     for (final FlutterDevice other : devices) {
       if (other == this) {
@@ -141,6 +142,7 @@ public static FlutterDevice getTester() {
     return new FlutterDevice("flutter-tester", "Flutter test device", null, false);
   }
 
+  @NotNull
   public String presentationName() {
     if (category() != null) {
       return deviceName() + " (" + category() + ")";

flutter-idea/src/io/flutter/view/FlutterView.java

@@ -705,7 +705,6 @@ private void replacePanelLabel(ToolWindow toolWindow, JComponent label) {
       if (contentManager.isDisposed()) {
         return;
       }
-      contentManager.removeAllContents(true);
 
       final JPanel panel = new JPanel(new BorderLayout());
       panel.add(label, BorderLayout.CENTER);