app: merge app/internal/wm into package app

The app and app/internal/wm packages are tightly coupled, requiring
quite a bit of forwarding types, values and constants from the internal
package to export it. Further, no other package imports package wm.

This change merges the two packages.

While here, drop the pre-Go 1.14 SIGPIPE workaround.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/Gio.java

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package org.gioui;
+
+import android.content.ClipboardManager;
+import android.content.ClipData;
+import android.content.Context;
+import android.os.Handler;
+import android.os.Looper;
+
+import java.io.UnsupportedEncodingException;
+
+public final class Gio {
+	private static final Object initLock = new Object();
+	private static boolean jniLoaded;
+	private static final Handler handler = new Handler(Looper.getMainLooper());
+
+	/**
+	 * init loads and initializes the Go native library and runs
+	 * the Go main function.
+	 *
+	 * It is exported for use by Android apps that need to run Go code
+	 * outside the lifecycle of the Gio activity.
+	 */
+	public static synchronized void init(Context appCtx) {
+		synchronized (initLock) {
+			if (jniLoaded) {
+				return;
+			}
+			String dataDir = appCtx.getFilesDir().getAbsolutePath();
+			byte[] dataDirUTF8;
+			try {
+				dataDirUTF8 = dataDir.getBytes("UTF-8");
+			} catch (UnsupportedEncodingException e) {
+				throw new RuntimeException(e);
+			}
+			System.loadLibrary("gio");
+			runGoMain(dataDirUTF8, appCtx);
+			jniLoaded = true;
+		}
+	}
+
+	static private native void runGoMain(byte[] dataDir, Context context);
+
+	static void writeClipboard(Context ctx, String s) {
+		ClipboardManager m = (ClipboardManager)ctx.getSystemService(Context.CLIPBOARD_SERVICE);
+		m.setPrimaryClip(ClipData.newPlainText(null, s));
+	}
+
+	static String readClipboard(Context ctx) {
+		ClipboardManager m = (ClipboardManager)ctx.getSystemService(Context.CLIPBOARD_SERVICE);
+		ClipData c = m.getPrimaryClip();
+		if (c == null || c.getItemCount() < 1) {
+			return null;
+		}
+		return c.getItemAt(0).coerceToText(ctx).toString();
+	}
+
+	static void wakeupMainThread() {
+		handler.post(new Runnable() {
+			@Override public void run() {
+				scheduleMainFuncs();
+			}
+		});
+	}
+
+	static private native void scheduleMainFuncs();
+}