Fix improper use of sub-monitor in Workspace.write()

[ptziegler]

SubMonitor.split() should not be called without providing any ticks, which might happen if the map of to-be-created files is empty. Given that the called method is private and only called from this method, the empty check can simply be pulled up.

[ptziegler]

!ENTRY org.eclipse.core.runtime 2 0 2025-03-29 13:51:52.240
!MESSAGE Attempted to create a child without providing it with any ticks
!STACK 0
java.lang.Throwable
	at org.eclipse.core.runtime.SubMonitor.logProblem(SubMonitor.java:1196)
	at org.eclipse.core.runtime.SubMonitor.newChild(SubMonitor.java:910)
	at org.eclipse.core.runtime.SubMonitor.split(SubMonitor.java:1121)
	at org.eclipse.core.runtime.SubMonitor.split(SubMonitor.java:1028)
	at org.eclipse.core.internal.resources.Workspace.write(Workspace.java:2832)
	at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.flushBatch(BatchImageBuilder.java:433)
	at org.eclipse.jdt.internal.compiler.Compiler.processCompiledUnits(Compiler.java:508)
	at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:358)
	at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:309)
	at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:442)
	at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.compile(BatchImageBuilder.java:250)
	at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:373)
	at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.build(BatchImageBuilder.java:118)
	at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildAll(JavaBuilder.java:311)
	at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:217)

[github-actions]

Test Results

 1 598 files   - 1   1 598 suites   - 1   1h 31m 1s ⏱️ + 5m 0s
 4 173 tests ±0   4 150 ✅ +1   23 💤 ±0  0 ❌  - 1 
11 998 runs   - 3  11 832 ✅  - 2  166 💤 ±0  0 ❌  - 1 

Results for commit f762d79. ± Comparison against base commit eca8380.

♻️ This comment has been updated with latest results.

[ptziegler]

The memory leak on Windows is unrelated and Linux/MacOS are looking fine. Merging.