Align impl doc block with impl keyword

Author: GuillaumeGomez

src/librustdoc/html/static/css/rustdoc.css

@@ -36,7 +36,7 @@ xmlns="http://www.w3.org/2000/svg" fill="black" height="18px">\
 	--button-border-radius: 2px;
 	--toolbar-button-border-radius: 6px;
 	--code-block-border-radius: 6px;
-	--impl-items-indent: 0.5em;
+	--impl-items-indent: 0.3em;
 	--docblock-indent: 24px;
 }
 

tests/rustdoc-gui/docblock-table-overflow.goml

@@ -16,6 +16,6 @@ compare-elements-property: (
     "#implementations-list > details .docblock > p",
     ["scrollWidth"],
 )
-assert-property: ("#implementations-list > details .docblock", {"scrollWidth": "832"})
+assert-property: ("#implementations-list > details .docblock", {"scrollWidth": "835"})
 // However, since there is overflow in the <table>, its scroll width is bigger.
 assert-property: ("#implementations-list > details .docblock table", {"scrollWidth": "1572"})

tests/rustdoc-gui/item-info.goml

@@ -19,7 +19,7 @@ store-position: (
     "//*[@class='stab portability']//code[normalize-space()='Win32_System_Diagnostics']",
     {"x": second_line_x, "y": second_line_y},
 )
-assert: |first_line_x| != |second_line_x| && |first_line_x| == 524 && |second_line_x| == 280
+assert: |first_line_x| != |second_line_x| && |first_line_x| == 521 && |second_line_x| == 277
 assert: |first_line_y| != |second_line_y| && |first_line_y| == 718 && |second_line_y| == 741
 
 // Now we ensure that they're not rendered on the same line.

tests/rustdoc-gui/notable-trait.goml

@@ -62,9 +62,9 @@ define-function: (
 // We start with a wide screen.
 set-window-size: (1100, 600)
 call-function: ("check-notable-tooltip-position-complete", {
-    "x": 685,
-    "i_x": 963,
-    "popover_x": 471,
+    "x": 682,
+    "i_x": 960,
+    "popover_x": 468,
 })
 
 // Now only the `i` should be on the next line.
@@ -78,8 +78,8 @@ compare-elements-position-false: (
 // Now both the `i` and the struct name should be on the next line.
 set-window-size: (980, 600)
 call-function: ("check-notable-tooltip-position", {
-    "x": 253,
-    "i_x": 531,
+    "x": 250,
+    "i_x": 528,
 })
 
 // Checking on mobile now.