Use JDT static inner class clean up for search plug-ins

This ticket uses and tests the "Use static inner class" cleanup feature:
 - It reviews the feature
 - It reduces the memory consumption as it avoids the pointer to the
outer class

Example:

Before:

public class Outer {

public class InnerClass {
    int i;

    public boolean anotherMethod() {
        return true;
    }
}
}

After:

public class Outer {

public static class InnerClass {
    int i;

    public boolean anotherMethod() {
        return true;
    }
}
}


Change-Id: If2fd5457666e4161e3eafa25893b0ec38d8eb36a
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.text/+/181576
Tested-by: Platform Bot <platform-bot@eclipse.org>
Reviewed-by: Alexander Kurtakov <akurtako@redhat.com>
diff --git a/org.eclipse.search/search/org/eclipse/search/internal/core/text/FileCharSequenceProvider.java b/org.eclipse.search/search/org/eclipse/search/internal/core/text/FileCharSequenceProvider.java
index 080ac46..1a2ef39 100644
--- a/org.eclipse.search/search/org/eclipse/search/internal/core/text/FileCharSequenceProvider.java
+++ b/org.eclipse.search/search/org/eclipse/search/internal/core/text/FileCharSequenceProvider.java
@@ -232,7 +232,7 @@
 		}
 	}
 
-	private final class FileCharSequence implements CharSequence {
+	private static final class FileCharSequence implements CharSequence {
 		private Reader fReader;
 		private int fReaderPos;
 
diff --git a/org.eclipse.text.quicksearch/src/org/eclipse/text/quicksearch/internal/ui/QuickSearchQuickAccessComputer.java b/org.eclipse.text.quicksearch/src/org/eclipse/text/quicksearch/internal/ui/QuickSearchQuickAccessComputer.java
index 9a29502..552bf46 100644
--- a/org.eclipse.text.quicksearch/src/org/eclipse/text/quicksearch/internal/ui/QuickSearchQuickAccessComputer.java
+++ b/org.eclipse.text.quicksearch/src/org/eclipse/text/quicksearch/internal/ui/QuickSearchQuickAccessComputer.java
@@ -85,7 +85,7 @@
 		return false;
 	}
 
-	private class LineItemQuickAccessElement extends QuickAccessElement {
+	private static class LineItemQuickAccessElement extends QuickAccessElement {
 
 		private final LineItem item;