[DevTools] Renaming Scripts panel to Sources panel

LayoutTests/inspector/extensions/extensions-panel-expected.txt

 CONSOLE MESSAGE: line 8: hello
 Tests WebInspector extension API
 
 Started extension.
 Running tests...
 RUNNING TEST: extension_testCreatePanel
 Panel created
 {
     createStatusBarButton : <function>
     onHidden : {
@@ skipping 12 matching lines @@
 }
 Panel shown
 Extension panel size correct
 Panel hidden
 RUNNING TEST: extension_testGlobalShortcuts
 Panel shown, now toggling console...
 Panel resized, switching away...
 Panel hidden, test passed.
 RUNNING TEST: extension_testOpenResource
 Showing .../extensions-panel.html
-Showing resource .../inspector/extensions/extensions-panel.html in panel scripts (scripts), line: 1001
+Showing resource .../inspector/extensions/extensions-panel.html in panel sources (sources), line: 1001
 Showing .../abe.png
 Showing resource .../extensions/resources/abe.png in panel resources (resources), line: 1002
 Showing .../missing.txt
 Showing resource .../extensions/resources/missing.txt in panel network (network), line: 1003
 Showing not-found.html
 log: Extension server error: Object not found: not-found.html
 Showing javascript:console.error('oh no!')
 log: Extension server error: Object not found: javascript:console.error('oh no!')
 RUNNING TEST: extension_testSearch
 Panel searched:
@@ skipping 19 matching lines @@
 Status bar buttons state:
 status bar item 0, icon: .../inspector/resources/button1.png, tooltip: 'Button One tooltip', disabled: false
 status bar item 1, icon: .../inspector/resources/button2.png, tooltip: 'Button Two tooltip', disabled: true
 Updated status bar buttons
 Status bar buttons state:
 status bar item 0, icon: .../inspector/resources/button1-updated.png, tooltip: 'Button One tooltip', disabled: false
 status bar item 1, icon: .../inspector/resources/button2.png, tooltip: 'Button Two updated tooltip', disabled: false
 button2 clicked
 All tests done.